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PC gets restart on running android studio emulator

I have installed andriod studio 3.6 latest version and then configured by setting environment variables.
When i actually run virtual device Pixel 3 emulator, my PC ran in to problem with blue screen.
Blue screen error message:
Your PC ran into a problem and needs to restart. Were just collecting some error info, and then you can restart.
How to resolve this ? what is the problem ?

Just remove from windows features:
HyperV
Virtual Machine Platform
Windows HyperVisor Platform
Install:
Intel(R) Hardware Accelerated Execution Manager (HAXM)

Install Intel x86 Emulator Accelerator(HAXM) solved my problem

I had the same problem and spend a lot of time trying to solve it. Finally find what was the problem - Windows update!
This Windows patches are causing the problem - KB4554354 and KB4549949
Updating the Windows to version 1909 (OS build 18363.836) fix the issue for me.
If you can't update windows to this version for some reason you can try to remove this patches.
You can rollback and uninstall your recent update follow these Steps:
Press Start button then click on the Gear icon which is the Settings
Press "Update and Security"
Press "View Update History"
Select "Uninstall Updates"
A pop up should appear then scroll down to the bottom then on the Microsoft Windows section, right click the recent or all of the "Update for Microsoft Windows KB4554354" then Click "uninstall".
wait for the process to be finished then restart the PC/Laptop there you should have the fix on your update problems.

This is just to share my experience that the blue screen has stopped for me too, by updating Windows 10 to the version 1909.
Though it is not talked about here, I have the impression that it is related to the Microsoft's Hyper-V and the Windows Hypervisor Platform (WHPX), made available in the year 2018.
For me, the emulator was working till late last year, without the Hyper-V acceleration (I cannot be more precise. I do not use it everyday).
Earlier this year, I installed the Docker desktop, which must have turned on Hyper-V. The Windows update(s) may have come around the time (though I do not find them here. They may be part of one of the cumulative patches). Then it must have become that the emulator wouldn't work anymore.
Hope it helps others who suffer from the same problem.

i think the emulator is not working properly ......uninstall the current emulator and install trusted emulators like blue stacks ........blue stacks will work in old pc's also

Visual Studio emulator for Android stuck at "OS is starting...", only on API Level 23 / Android 6

Since I read the news about Xamarin now being "free", I immediately installed Visual Studio 2015 Update 2 and the Android tooling (NDKs, SDKs for 19-23, Visual Studio Emulator for Android dated January 2016) to start working on an Android application.
Excited I launched the emulator from Tools -> Visual Studio Emulator for Android and installed the profile that is the best match for my own phone. Since my phone is on Android 6, I decided to get a profile for API Level 23 / Android 6.
Since I had already enabled Hyper-V a few months ago, the installation for the profile only had to add me to the Administrators group and create 2 network adapters.
So far, so good.
Upon starting the emulator, it would stay at "OS is starting...". I figured I'd wait a while. I figured I'd wait a while longer too. After that, I gave up the possibility of it going to work and started investigating.
I also tried other profiles, a few others from API Level 23, one from 22 and one from 19. Only the ones from API Level 23 did not work.
The following steps are what I came up with so far by Googling etc. I tried them in all sorts of combinations:
Rebooting
Disabling / enabling Hyper-V
Removing vEthernet adapters (through the Hyper-V Manager).
Running XDECleanup
Allowing XDE through my Windows Firewall as application (incoming)
Restoring the emulator software in Programs and Features
Enabling / disabling "Processor Compatibility" in Hyper-V Manager.
This is the data I've gathered so far:
A screenshot of the error message that the emulator gives after waiting a long time (10 - 15 minutes, maybe a little longer)
A screenshot of the last part of the log when being connected to the Android 6 VM:
A screenshot of the last part of the log of a working VM (this one's from an Android 4.4 VM):

Responses I've got so far from Microsoft:
-Those errors are normal
-And the only step I've tryed which they told me to, and I don't see here, it's this one:
On Hyper-V Manager, check the option for compatibility under CPU section
Besides from this, just make sure that on Hyper-V you get only 2 switches, the one you use to connect to the internet and the one that the VS Emulator for Android creates, I haven't got any results, but if you try, maybe you will.

In my case, I was mucking around with the VS emulator's virtual switches and had the network adapters in the wrong order.
After I moved the Windows Phone Emulator Internal Switch (Created when first running the VS Emulator) to the first Network Adapter slot in my settings, the emulator started up just fine. Apparently, order matters.

Had the same problem but got mine to work after trying a lot of things from different threads.
In the end I think this did the trick for me:
I added "c:\Program Files (x86)\Microsoft XDE\10.0.10586.0\xde.exe" as an exception in the firewall.
(i also switched of the firewall, but was probably unnecessary)
Temporarly disabled the WiFi device
Uninstalled VirtualBox
Removed all Virtual Switches in Hyper-V
Executed XdeCleanup.exe
Started the emulator again and it started up successfully!
Swiched of the emulator and enabled Firewall, Wifi device.
The emulator still starts successfully every time!
Thanks to all for sharing!

If you're using Xamarin, it's recommended that you use Xamarin Player. It's not Xamarin exclusive, it's just a much faster Android emulator. I use Android Studio, and the Xamarin Player is still faster on boot and launch than the default. This is just my recommendation to you, I have no clue how to fix your Visual Studio emulator, sorry.

I've played a lot with this and realized that I have had manually configured paging file on Windows. After restoring it to default all worked perfectly without messing with the virtual switches or adapters.
Just make sure that you have all Windows memory etc. settings set to default.
Regards, Mladen

My problem was that the system image was missing for the emulator.
When I opened the android virtual device manager it had an exclamation mark next to actions(i had to download the system image via the download link).

I had the same error message. The solution for me was:
Uninstall all emulators in the Visual Studio Emulator for Android
Check in Hyper-V-Manager if there also no instances
Unistall Visual Studio Emulator for Android
Run xdecleanup.exe (C:\Program Files (x86)\Microsoft XDE)
Uninstall Hyper-V from Windows features
Removed virtual ethernet adapters through uninstalling in Device Manager
(be sure to display disabled devices too)
Install Hyper-V from Windows features
Install Visual Studo Emulator for Android again
Download and install your emulator/profile
Run the emulator and have fun :-)
It seems there was a problem with the virtual switches and Hyper-V. The correct settings for the adapter looks like these:
Hyper-V-Manager:
Device Manager:
Network adapter:
Ethernet:
vEthernet (Virtueller Switch: Intel(R) Ethernet Connection (2) I219-LM #2):
vEthernet (Internal Ethernet Port Windows Phone Emulator Internal Switch):
Emulator network settings:

App not run in visual studio emulator for android in visual studio 2015

I create blank xamarin android project without add any code when i debug this project debugging without problem but when i run app with visual studio emulator for android emulator is running but not starting my app and deploy failed and don't show me error
why ?
please help me

I had the same issue. VS 2015 can launch the VS emulator but can't deploy the app.
I was able to solve the issue like this:
Launch the emulator (F5 in VS, then cancel the deployment using the Build/Cancel menu)
Click on the chevron icon (») in the toolbar to the right of the emulator
Select the Network tab
Locate the preferred network ip address
Back in VS, click on the Open Adb Command Prompt toolbar button
Type adb connect [the emulator ip address]
Press F5 again in VS
Looks like a VS bug to me.

I had the same issue. It turned out the root cause was that the VS Emulator couldn't find adb.exe.
When that happens it won't connect to the emulator unless you do the manual connection following the steps CSharpRocks gives. The emulator also won't be listed under "adb devices".
The fix for me was to reinstall the Android SDK, using the Windows EXE based installer (not the zip installer). The EXE installer sets the HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Android SDK Tools key, Path value, in the registry, pointing to the Android SDK root directory.
The VS Emulator uses that registry setting (or the Android Studio install registry setting) to find the SDK, assuming you didn't install the Android SDK with Visual Studio itself. With that, it should be able to find adb.exe and work.

Have a look here:
Xamarin Forms Android App Crashes Running Debug with VS Android Emulator
Start the Hyper-V manager
Select the emulator you are trying to use
Right-click, hit settings
Click processor
Click Compatibility
Set checkbox “Migrate to a physical computer with a different processor version”

I'm having a very similar issue. I have found two different kind-of-work-arounds, but have not yet figured out a full solution.
Start the emulator before trying to deploy to it
Launch the Visual Studio Emulator for Android application from the start menu.
Launch one of the available emulators via the green arrow
Attempt to again launch your application from visual studio, selecting the VS Emulator N-inch... emulator from the drop down menu
For me for some reason the app still doesn't "launch" on the emulator, although it is installed. So I have to open the application menu and select my app. Additionally it will usually crash the first several times I try to open it, but eventually displays my single default label, Welcome to Xamarin Forms!.
Run the application in Ad-Hoc mode
Before running the application, change the solution configuration (from the top toolbar next to the green "run" button) to Ad-Hoc.
The problem with both of these methods though is that I'm still not able to actually debug an application. I can run it, but my breakpoints are ignored and I think that will make finding bugs difficult once I actually start to write a real application.
I hope to update this answer once I figure out an actual solution.

I had the same problem yesterday. The problem appeared (probably) because I tried to start development after a long break. I updated VS and everything, but faced many issues.
Eventually you need to start fresh
Make sure SDK for emulator points to the right place (HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Android SDK Tools)
Run Visual Studio with Administrator privileges
Go to Hyper-V Manager and delete ALL Virtual Switches - let the system recreate them when needed. It will do it properly
Delete all existing emulators and recreate them in Visual Studio. I even found a comment to name them without spaces - not sure if it is needed, but wouldn't hurt.
Doing all this helped me. But I was on the verge of reinstalling Windows 10 clean. I think lots of things and configuration changed and are no longer compatible.

Try it enabling Hyper-V and using a Visual Studio Emulator from android; that worked for me after a lot of attempts and research

I had the same issue but in my case it was not the registry. After doing a release build, I deployed the app to the emulator device in release mode which pushes the app to the device and then effectively "disconnects". This leaves a version of the app on the device which seems to block further attempts at debugging or deploying.
I solved it by starting the emulator, going to "settings -> apps" and manually uninstalling my app. Then the next debug build & deploy worked again.
You could probably also manually start the emulator and say "wipe device" option so it starts fresh.

In VS2017, on a Windows10 machine, all I had to do to get the app to show up was turn off Mobile Data.
(swipe down or use settings, then click Mobile Data and confirm to turn it off).
After I turned it back on, I could access the app. Before doing this, it always seemed that the emulator ran, but wouldn't run the app.
... no idea why this worked, but I'm posting it here in case it helps someone.
During my troubleshooting process, I also looked at these articles:
VS Android Emulator wont run application
Troubleshooting the Visual Studio Emulator for Android
Update Your Path For The New Android Emulator Location

Install apache in VS 2015 here.
Visual studio requires apache to develop android apps.
You also may want to look at some other suggestions:
notshowing, troubleshooting

I had such issues before with the android SDK emulator, now I'm using Genymotion emulator instead of it, it is more light and faster and will be detected automatically by you VS once launched.
you can download the free version from here : https://www.genymotion.com/
and also you can download any device emulator.

Visual Studio Android Emulator won't run application

I recently got into Xamarin development. I have a lot of experience in Xcode making iOS apps and the iOS side was very straight forward. Now I'm trying to implement Android. I downloaded a Hello World example to get my bearings. When I run it I have no problems getting the simulator to show up (MonoForAndroid_API_10 and MonoForAndroid_API_12) but the actual application doesn't run, and does not show up anywhere on the simulator. Essentially whenever I use run or run with in Xamarin on Android, it pulls up a fully functioning, albeit empty simulator.
How do I get my application to run on the emulator?

Like the other commenters, this is most likely just a symptom of slow emulator on your machine. I'm running Xamarin-Android development on my 2010-era OSX machine in mavericks with 8GB RAM, and it is slow-slow-slow, but usable. Try to find the Intel x86 speeds improvements (look for HAXM) and you will find that the emulator will be much much faster.
And yeah, get a real handset and plug it in to your computer: always much faster than emulation.
later edit Get Genymotion for Mac OSX or for PC/Windows or PC/Linux. It's way way way faster than the other emulators. I have since found that this is as fast, or faster, than running the App on my connected Android phone. It's certainly simpler in not having to have the device plugged into one of my USB ports, and allows me to code and test on the train. http://www.genymotion.com/

Don't know if my issue was the same but finally this troubleshooting helped me to run emulator https://msdn.microsoft.com/en-us/library/mt228282.aspx#ADB.
I was missing key Android SDK Tools with string value Path in registry Computer\HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node
I've created it manually and it worked.
UPDATE
Before I got the issue with running emulator, I couldn't see it in Visual Studio. The reason was I've installed VS Android Emulator through standalone installation, not through VS Installer. It had to be installed there as well.

I had the similar issue, and then I deleted the existing device simulator and reinstalled again and it started working.

As I use a different SDK, in my case
Go to Tools > Options > Xamarin and set the Android SDK path.
Sometime Visual Studio changes this configuration;

2020 Update:
I followed the most voted comment, however, with Visual Studio 2019 updated recently, the steps have changed a little. Here is what previously worked:
WHAT WORKED BEFORE
"Don't know if my issue was the same but finally this troubleshooting helped me to run emulator https://msdn.microsoft.com/en-us/library/mt228282.aspx#ADB. I was missing key Android SDK Tools with string value Path in registry Computer\HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node
I've created it manually and it worked."
WHAT TO DO INSTEAD
Nothing. Don't mess with the path.
WHAT WORKED BEFORE
"Before I got the issue with running emulator, I couldn't see it in Visual Studio. The reason was I've installed VS Android Emulator through standalone installation, not through VS Installer. It had to be installed there as well."
Previous instructions image
WHAT TO DO INSTEAD
a. Go to Tools located at the top of the VS window, Get Tools and Features, go to Individual components, using the search tool in the pop up box, search "emulator", once you get the result, make sure both Google Android Emulator (API Level 25)(local install) and Intel Hardware Accelerated Execution Manager (HAXM) (local install) are both checked.
b. Close the solution(s) and restart VS then reopen the solution(s).
c. To deploy the app on the emulator, click Start button to spin up the emulator, left click on your Android project, then click Deploy. You should be able to see your app on your emulator's app menu.
Updated Instructions image

Worked for ME
Sometimes you close the android Emulator but not POWEROFF the Emulator.
this problem happens when emulator shutdown un-properly.
Restart Your EMULATOR
First start your emulator
Then restart your emulator by pressing down the power button and select restart option in your android emulator.

I enabled Hyper-V acceleration based on microsoft documentations: https://learn.microsoft.com/en-us/xamarin/android/get-started/installation/android-emulator/hardware-acceleration?tabs=vswin&pivots=windows#accelerating-with-hyper-v
Basically you need to turn on these two windows features from the control panel (Turn windows features on of off):
Hyper-V.
Windows hypervisor platform.
then from visual studio go to: Tools >> Android >> Android SDK manager >> Tools >> make sure that "Android emulator" version is 27.0.1 or higher, if not, you will find in the same screen a button below to update it.
I did this on windows 10 64-bit, with VS 2017 Community 15.9.5

Why emulator is very slow in Android Studio?

I just setup Android Studio on my PC, which is new launch to develop Android application.
My problem is that, when I try to run my small app in emulator, it take to much time to launch and after then emulator is working slow too.
AVD settings
AVD Name: Glaxy
Device: Glaxy Nexus (4.65", 720x 1280: xhdpi)
Target: Android 4.2.2 - API Level 17
Memory Option: Ram 500, VM Heap 64
Internal Storage: 200MiB
I have good window pc: Intel Core 2 Duo 2.93Ghz and Ram is 3gb
I am new in Android development and java.

The Best Solution is to use Android Emulator with Intel Virtualization Technology.
Now if your system have a Processor that have a feature called as Intel Virtualization Technology, then Intel X86 images will be huge benefit for you. because it supports Intel® Hardware Accelerated Execution Manager (Intel® HAXM).
To check that your processor support HAXM or not : Click Here
You need to manually install the Intel HAXM in your system. Follow these steps for that.
First of all go to - adt -> extras -> intel -> Hardware_Accelerated_Execution_Manager
Make sure that Intel Virtualization is enabled from BIOS Settings.
Now install Intel HAXM in your system and select amount of memory(i prefer to set it as default value).
After installation create new Android Virtual Device (AVD) which should have a Target of API Level xx
Now set the CPU/ABI as Intel Atom(x86).
If you are on Windows then do not set RAM value more than 768 MB while setting up an emulator.
Run the emulator. It will be blazing fast then ordinary one.
Hope it will be helpful for you. :) Thanks.

Just edit the AVD settings as below,
Enable snapshot options and please use INTEL HAXM software for speedup.just visit https://software.intel.com/en-us/articles/intel-hardware-accelerated-execution-manager-intel-haxm and download...

I tried all the suggested remedies and none had any impact. The Android Studio emulator experience was simply unusable with my setup (Windows 10, AndroidStudio 3.5, Quadcore 3.2 Ghz, 32GB with SSD drive).
I tried Updating Studio, Installing Intel HAXM, Changing the memory settings via SDK, using an actual device, excluding the various folders from in the Windows Anti-virus among other things.
The solution that made it work like a breeze was to exclude the Android Debug Bridge (adb.exe) "as a process" from the Windows Security / Virus Protection. You can either do it yourself or read the details below to know how to do it.
I suggest verifying the severity of the speed issue yourself. The same will be used to verify the difference immediately after you apply the remedy. Running the options from within Android Studio just makes it more complex.
Steps to check the issue:
Get the path for your Android SDK Tools. You can find it from SDK Manager -> Appearance and Behavior -> System Settings -> Android SDK.
Open a command prompt or terminal window. You can do right click on Windows (Start) Icon -> Run and execute "cmd". This should give you a windows command prompt or terminal window.
In the terminal window, change your drive and path to your Android SDK folder using the CD command. Now change to the sub-folder Platform-tools.
You will find the Android Debug Bridge (adb.exe) in this folder. This plays a very crucial role in operating the emulator as well as the actual device.
In the terminal window, execute the adb.exe tool with the command adb. It should instantly return back with the help parameters for adb.
Now execute adb.exe with a command like - adb devices. This should simply stall and take several seconds to come back with the information even if you have no devices or emulator running. In my setup it took almost 30 seconds. This is the issue.
Anything you do with the emulator goes via adb and gets stuck here. Once the remedy is applied, it should execute the adb devices command as instantly as the simple adb command without any parameter.
Steps to remedy:
Go to Windows "Virus and Threat Protection" setting. There are several ways to reach it. You can use Right Click on Windows (Start) Icon and choose Settings. Choose Update & Security, then Windows Security, then Virus and Threat Protection.
You will find the option Virus and Threat Protection Settings. Select it. You will find several options, look for Exclusions. Select the option Add or remove exclusions. This will take you to the list of Files, Folders, Processes which are presently excluded by the windows anti-virus. It may be empty or may have some data.
Select "+ Add an Exclusion". You will find 4 options - File, Folder, File Type and Process. This is critical. Please choose Process.
In the "Enter Process Name" input box type in the name adb.exe. Please dont forget to type in the extension, just putting adb will not work. Accept the input with "Add" button.
You are done. Now goto the command prompt again and follow the same steps you did earlier to check the issue. Hopefully you will be pleasantly surprised and your entire Android Studio emulator experience should become seamless.
Note that the steps may slightly vary depending upon your version of Windows, Android Studio and SDK tools however it should still apply.

The new Android Studio incorporates very significant performance improvements for the AVDs (emulated devices).
But when you initially install the Android Studio (or, when you update to a new version, such as Android Studio 2.0, which was recently released), the most important performance feature (at least if running on a Windows PC) is turned off by default. This is the HAXM emulator accelerator.
Open the Android SDK from the studio by selecting its icon from the top of the display (near the right side of the icons there), then select the SDKTools tab, and then check the box for the Intel x86 Emulator Accelerator (HAXM installer), click OK. Follow instructions to install the accelerator.
Be sure to completely exit Android Studio after installing, and then go to your SDK folder (C:\users\username\AppData\Local\extras\intel\Hardware_Accelerated_Execution_Manager, if you accepted the defaults). In this directory Go to extras\intel\Hardware_Accelerated_Execution_Manager and run the file named "intelhaxm-android.exe".
Then, re-enter the Studio, before running the AVD again.
Also, I found that when I updated from Android Studio 1.5 to version 2.0, I had to create entirely new AVDs, because all of my old ones ran so slowly as to be unusable (e.g., they were still booting up after five minutes - I never got one to completely boot). As soon as I created new ones, they ran quite well.

Check this: Why is the Android emulator so slow? How can we speed up the Android emulator?
Android Emulator is very slow on most computers, on that post you can read some suggestions to improve performance of emulator, or use android_x86 virtual machine

As #Xavi mentioned, Android Emulator is normally slow and lags a lot. Either test your app on an actual device or use an alternative emulator such as BlueStack or Android-X86.
Another tip for using emulator is to not close if you ain't done testing your application. Just leave it open. In this case you skip the time it takes to launch.

Use x86 images and download "Intel Hardware Accelerated Execution Manager" from the sdk manager.
See here how to enable it: http://developer.android.com/tools/devices/emulator.html#accel-vm
Your emulator will be super fast!

The emulator is much much faster when running on Linux. In Ubuntu 13.04, it launches within 10 seconds, and it runs nearly as smoothly as on a physical device. I haven't been able to reproduce the performance on Windows.
EDIT:
Actually, after the first boot, when using the Atom arch. and GPU acceleration, the Windows emulator runs nearly as well as in Linux.

Try increasing your ram of intel HAXM by reinstalling it..
Worked for me..
In my pc HAXM setup's location was here:
C-Users-Pc's_name-AppData-Local-Android-sdk-extras-intel-Hardware_Accelerated_Execution_Manager

Check this list:
install Intel HAXM
just use x86 AVD
use small size screen

I tend to load AVD through snapshot which can be setup in the AVD Manager > Choose AVD > Details... > Checking Emulator Options: Snapshot, and then to run the AVD, Select AVD in AVD Manager > Start... > Select Save To Snapshot and Launch from Snapshot. The first time, ensure that save to snapshot is chosen, as no snapshot exists to launch. The next time onwards choose launch from snapshot.
Slightly apprehensive to suggest this as well, but I have noticed a peculiar behavior when loading and running AVD. When I have the laptop battery being charged on my Lenovo laptop - 64 bit Windows 7, 4GB, 2.5GHz machine, the emulator loads and runs slightly faster and also lags less. I wonder if it is the configuration on my laptop to slow down high computational processes. Would be nice to know if someone else has noticed this behavior? Unplug the charger when the AVD is loaded and see if the AVD slows down.

A quick fix if using Android Studio (or Eclipse) is to disable the boot animation.
1) Select Run > Edit Configurations
2) Android Application > YOURAPP
3) Select the "Emulator" tab and check the "Disable boot animation"
This is will stop the "ANDROID" image from loading and boot directly to the lock screen, then keep your the emulator open. Also, to avoid problems, don't rotate the device before launch (Cmnd + Ctrl + F11), and don't try to run the app more than once during installation.

Android Development Tools (ADT) 9.0.0 (or later) has a feature that allows you to save state of the AVD (emulator), and you can start your emulator instantly. You have to enable this feature while creating a new AVD or you can just create it later by editing the AVD.
Also I have increased the Device RAM Size to 1024 which results in a very fast emulator.
Refer the given below screenshots for more information.
Creating a new AVD with the save snapshot feature.
Launching the emulator from the snapshot.
And for speeding up your emulator you can refer to
Speed up your Android Emulator!:

Try using another android virtual device. You can create one by adding a new device by going to the AVD Manager. Select the screen size 3'2 and API-10 (gingerbread).
This worked for me, and it is super-fast now.
P.S.- My laptop used to take forever to load the emulator, and It never got started due to insufficient memory(4.2). I used to get restart again and again. This solved my problem.

Google Launches Android Studio 2.0 With Improved Android Emulator And New Instant Run Feature
New Features in Android Studio 2.0 :
1.Instant Run: Faster Build & Deploy
You can quickly see your changes running on your device or emulator.
Enable Instant Run follow this steps:
1.open Settings/Preferences
2.go to Build, Execution, Deployment
3.Instant Run. Click on Enable Instant
Please see this video of Instant Run --> Instant Run
2.GPU Profiler
For developers who build graphics-intensive apps and games, the Studio now also includes a new GPU profiler. This will allow developers to see exactly what’s happening every time the screen draws a new image to trace performance issues.
click here for more details about the GPU Profiler tool
Getting Started Guide for Android Emulator Preview
For more detail about android 2.0 Biggest and best update of 2015 you can see very good article Author by #nuuneoi :
First Look at Android Emulator 2.0, the biggest and the best update yet in years

In my case, the problem was coming from the execution of WinSAT.exe (located in System32 folder). I disabled it and issue solved.
To turn it off:
Start > Task Scheduler (taskschd.msc)
Find Task Scheduler (Local)
Task Scheduler Library
Microsoft > Windows > Maintenance
Right click WinSAT
Select disable.
The Reference
Also, suppress it from Task Manager or simply reboot your machine.
Point: In this situation (when the problem comes from WinSAT) emulator works (with poor performance) when you use Software - GLES 2.0 and works with very very poor performance when you use Hardware - GLES 2.0.

Aside from what everyone has already said about HAXM and other configuration settings as solutions for this problem, my solution had nothing to do with software configuration or processor limitations.
I setup Android studio on an older HDD and I had Visual Studio running an android emulator on an SSD. My bottleneck was the old HDD - the SSD I had resulted in more speed.
The solution - albeit not the best for you - is to look in installing an SSD. This is not a very feasible solution in 90% of the cases but for me the root cause was linked to my hardware - not my software config.
Hope this helps another person facing a similar problem!

This worked for me. My size on disk was just too high for the emulator to run correctly. Wiping the data took it from 4.9 GB to 2.9 GB.
Click on the AVD manager at the top right and it will pull up a screen with all your devices. In row with your device the very last icon will be a drop down arrow, click it. Click 'Wipe Data' then 'Cold Boot'

For those who enabled HAXM and the emulator still works slow here is what you should do:
If Avast antivirus is running on your computer, it is most likely the culprit.
as per HAXM Release_Notes.txt (Version 7.5.2):
On Windows, Avast Antivirus may interfere with HAXM and cause Android Emulator or QEMU to run very slowly. A workaround is to uncheck "Use nested virtualization where available" in Avast Settings > Troubleshooting.
So open your Avast dashboard > Menu > Settings > Troubleshooting and disable "Enable hardware-assisted virtualization"
Give a higher priority to your emulator's process in the Task Manager:
Locate your emulator's process in the Task Manager > Details tab:
Right-click on it and Set Priority -> Above normal
Sorry that the screenshot is not in English but you got the point, right?
That helped me significantly! I hope it will help you as well.
Also, one thing as per the Release Notes:
On Windows 8, 8.1 and 10, it is recommended to disable Hyper-V from Windows Features in order for the HAXM driver to properly function.
In my case, I didn't have any "Hyper-V" feature on my Windows 8.1 but you probably should try it, just in case. To locate and disable that feature see this article: https://support.bluestacks.com/hc/en-us/articles/115004254383-How-do-I-disable-Hyper-V-on-Windows-

This is probably because incomplete files in your sdk . Sometimes firewall of ur office or somewhere blocks it and hence error message comes saying peer not authenticated I was facing the same problem but after downloading all the files by getting firewall access
My emulator is working properly and much faster than before