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Android SDK is missing, out of date, or is missing templates. Please ensure you are using SDK version 22 or later

Possible duplicate, I just download a Android Studio Zip file like Eclipse, as I opened getting this error.
But problem is how to update it?

same problem happened to me, From this
I have faced the same issue, to solve it:
1- delete (or move) the projects folder (AndroidStudioProjects).
2- Run the Android-Studio (a WELCOME screen will started).
3- From Welcome Screen choose, "Configure -> Project Defaults -> Project Structure)
4- Under Platform Settings choose SDKs.
5- Select Android SDK -> right_click delete.
6- Right_click -> New Sdk -> Android SDK -> choose your SDK dir -> then OK.
7- Choose the Build target -> apply -> OK. enjoy

I had same issue in Android Studio 3. (the project was open) so I closed the current project and the IDE automatically prompted to download the latest components. once its done everything was working correctly.

Here's a better approach where you don't have to delete/move anything for Android Studio 3.+.
Open Android Studio and click cancel/ignore for error prompts on missing SDK for each project.
Close all your open projects. You can do this by File > Close Project.
After you do step 1 for all projects, the Welcome screen appears.
The welcome screen will detect you are missing the SDK and give you options to fix the problem, i.e., install the SDKs for you.

Click on Tools > SDK Manager or click SDK Manager
after If you are unable to see the location of your Android SDK Location, click on edit and create a folder where you want to keep it and then click Next and Finish

Source: https://stackoverflow.com/a/46351772/13093413
(Top right corner) File > Close Project > After you close the project you will get a screen which says that you don't have an sdk and will ask you if you want to install it.

I was able to trigger an SDK download like this:
Close Android Studio
Open android studio, but be ready
Once you see "loading project", click cancel. (this will only appear for seconds on a fast machine)
The SDK download window appeared!

If Android Studio directly opening your project instead of setup window, then just close the windows of all projects. Now you will able to see the startup window. If SDK is missing then it will provide option to download SDK and other required tools.
It works for me.

Create SDK folder at \Android\Sdk
Close any project which is already open in Android studio
Android Studio setup wizard will appear and perform the needed installation.

Press escape to close all errors.
close project
Android studio will prompt to install SDK
Install the SDK and configure project

1.Click on Configure
2.Then Choose Project Defaults
3.Click on Project Structure
4.Set android sdk path
You will find here "C:\User\YourPcname\AppData\Local\SDK"
Note: Sometime AppData may hidden if it will not show then enable show hidden content.
5.Apply Changes
6.Then Select Sdk From Configure option
7.Then Android sdk manager page is open
8.In bottom you will see Install packages option
9.Install them and enjoy.

Unable to resolve target 'android-18' error

i am unable to download target android-18 file

In ``default.properties` file .
set target=android-18.
Check also that you installed this API level and check it in properties window, like:
In my case 17 is selected

Right click on your project select Properties(Alt+Enter),
goto Android(Project build Target)-> Check Android 4.2.2 or earlier version which you have, click on Apply-> OK, that's it.
finally clean your project, Done!!

First open Android SDK Manager and check whehther API18 (Android 4.3) SDK platform is downloaded or not. If not download it by selecting check box then accept license and press install package.
Next close and open eclipse again.
now it will show API18 (Android 4.3) SDK platform in Android SDK Manager as installed.
after that select project -> Properties -> Android -> mark checkbox Android 4.3 in project build target ->apply ->ok.
select project -> project-> clean.

I thing u r importing Project in eclipse some Android Project Not Find Target sdk So we Add target sdk like Right Click on ProJect GO To Properties GO to Android and Select Taget if Not Install than Download Adt plugin For Eclipse

The error is well justified, either you dont have correct properties added or you are missing the SDK.
Please check this link,
Unable to resolve target 'android-XX'
Hope it helps

Import project in Android Studio from Eclipse

I installed new Android Studio 0.1.1 based on IDEA ide and tried Import code from Eclipse.
Go to Eclipse->Export->Grandle so it add gradle file
Open Android Studio and select Import Project and select my project folder with build.gradle file
Press Finish and get an Error: failed to find target android-15 (this is was parget of my project)
I go to system variables and change to %ANDROID_HOME% = d:\dev\android\android-studio\sdk\ (remove platform-tools from path)
And get new error: failed to find Build Tools revision 15.0.0
Also create another New Project and change Android SDK for it, but I still cant import project
I explore this problem and find the weak point: in file build.gradle I change next lines:
from compileSdkVersion 15 to compileSdkVersion "17"
from buildToolsVersion "15" to buildToolsVersion "17"
And it fix my problem with project import. I think it's problem in Eclipse export function. Build tools starts only from version 17 (in ADT 22), so it's imposible to find version 15.

Had same problem, now works. I did this:
Open android studio:
Tools -> android -> SDK manager then install the android 4.0.3 (API 15) and done.
It worked for me.

These simple steps worked for me:
Open new project (new not import)
Press F4
On the left Click on SDKs
Delete all SDKs
Click on +
Choose the SDK you are using for eclipse
Choose the right version
Click OK
Open your project using gradle file
Enjoy :)

This is an import problem. NOT an SDK Level issue.
You need version 22 of the SDK Manager before you attempt the export or it won't be in a format that Android Studio can consume.

Do you have updated SDK for Eclipse?
You need the Rev.22. After you downloaded it, you can Export the Project with a "build.gradle".
Migration of the Projects
Updating your SDK

Update SDK go to config settings, project settings then you will see SDK that isn't correct point to same place eclipse points to for SDK.
Worked for me.
Also it might help to reexport the project with new sdk

Update your android APIs using Android SDK Manager.It seems you have installed API lower than level 15.

For general 'import project' info, search for the word 'import' on
this install-guide document for Android Studio:
http://developer.android.com/sdk/installing/studio.html
EDIT: I've recently learned to use the 'import' dialog, so that I can
import projects from GitHub, which is very cool! (I first watched a tutorial
on YouTube titled 'git and github'). Then I learned that one needs to
use 'git' to "Clone" an entire GitHub repository (to bring a dir-tree full
of separate projects to your development machine). Then, you can navigate
into that sub-tree, to a given project of interest, and then use Android
Studio's 'import' dialog to play with that example project.
WOW, NEAT!
Hope this helps...

Had the same problem when Android studio 0.2.9 on mac and importing an old eclipse project:
By default, it uses /Applications/Android Studio.app/sdk as the android sdk location, instead of whatever you used to use.
On a per-project basis, you can go to the menu's File->Project Structure (command-;) and on the left you can change the project's sdk location.
To handle all projects (new or imported), before opening anything at the start screen click configure -> Project Defaults -> Project Structure -> (on the left) Android SDK to do the same. (re: https://stackoverflow.com/a/18409923/954643)
If you were starting from scratch without any android sdk setup and eclipse though, you'd have to download the missing SDKs via Tools->Android->SDK Manager.

I simply solved the problem by changing the project build target (Project properties->Android->Project Build Target).

In the file build.gradle change your compileSdkVersion to your current version. For me it is 23. Your buildToolsVersion would be the same number. Hence the only thing I had to do was
Change CompileSdkVersion 15 to CompileSdkVersion 23 in the build.gradle

From the quick start window, choose Configure, then choose Project Defaults, and then choose Project Structure. Then on the left under Platform Settings choose SDKs. Then to the right of that choose the current android platform, mine was Android 4.2.2 Platform, and delete it using the red minus button at the top, then add a new android platform using the green plus button at the top and point it to your current SDK folder and that is it.

Unable to resolve target 'android-8'

Long story short, eclipse updated ADT & SDK to v20 , which I didn't like and wanted to get back to 18.
So I uninstalled ADT and SKD and donwloaded v18 from
http://dl.google.com/android/installer_r18-windows.exe
and http://dl.google.com/android/ADT-18.0.0.zip
Installed both of them, yet now Eclipse can't seem to find some sdk platform and throws the "Unable to resolve target 'android-8'" error... any ideas what might be wrong?

in android sdk window go to:
tools >> options
will be open a new window and check the option force https:// ....
disable this checkbox
if your network is using proxy conigure it in this window too.
reload or restart the android sdk window and try download again. :)

Right click on project->properties.
Select Android on left panel.
If you see Android 4.0.3 in (Project Build Target), then tick it and click Apply button.
If you don't have 4.0.3 version in Build Targets, then you should install it. to install simply go to sdk manager and click on Android 4.0.3(API 15)-SDK Platform.

Open "Android SDK Manager"
Go to Menu: "Tools -> Options..."
Press the button "Clear Cache"
Press the button "Close"
Close "Android SDK Manager" (not necessary!)
In Eclipse, go to Menu: "Project -> Clean..." to refresh current project

simple set your project's target sdk as shown in below screen shot

unable to get system library for the project on eclipse ide

I was working on an android tutorial and it wanted me to import the library from another project .The import worked and the project works correctly. But I noticed that doing that messed up several of my other projects (the ones that use Android 2.1) by apparently messing with the build path. Now instead of seeing "Google APIs [Android 2.1]" under the gen folder I see "Unable to get system library for project".
I verified the following:
I right-clicked the project and went to Properties I see that the correct Project Build Target is checked(Google APIs [Android 2.1]), but "Unable to get system library for project" is still shown above the assets folder and below gen and Android Dependencies. Cleaning all projects doesn't help.
How can I fix this problem?
is there a way to fix this issue globally or do I have to do it one by one?

I had the same problem. Try
Right click on your project
Go to properties
Click the Android section
Select a different target api (assuming one is already selected, as mine was - otherwise, select the one you want and jump to step 9)
Click OK
Do steps 1-3 again
Select your original target api
Click OK
Clean and build your project
Worked for me, anyway.
Derived the solution from:
"Unable to get system library for project" after I upgraded to Android SDK 2.3 and ADT 8.0

Error in .classpath on your project. It not connect to android sdk. Fix it and clean project. :-)

This happens when you are targetting an API version that for some reason is not mapped on your buildpath.
See which is the version of the SDK you are pointing to at the project.properties file.
Go to the SDK Manager at Window->Android SDK Manager
Check the Android API item that matches the version you want to use, OR, click on the latest one and then update your project.properties file.
Make sure your project build configuration is Project->"Build Automatically"
Retsart Eclipse (claning and rebuilding may not refresh all the project properties)

Borrowing from #Erhannis answer :
"
Right click on your project
Go to properties
Click the Android section
"
When I view the build target everything looked fine :
So I checked another build target , hit apply, and then re checked my original build target (Android 4.4.2) and re-hit apply. My project then compiled.

For me the project.properties file was missing (it was code from a repo I checked out). So I just created one with this line:
target=android-20
After that, Erhannis' solution worked for me.

Just for completing Erhannis answer: If you fixed the problem but it appears again when you restart Eclipse, then just go to the file local.properties on your workspace folder and verify that the location of the Android SDK there is correct.

At times, when only single Android SDK version is installed on your system, and if it gets changed either by un-installing / re-installing Eclipse, or otherwise (directly through SDK Manager), then this issue might crop up.
.
This is accompanied by the message like this on Eclipse console:
YourApp] Unable to resolve target 'android-22'
.
A simple workaround to this issue is:
Open AndroidManifests.xml of the project, and in the:
<uses-sdk
android:minSdkVersion="14"
android:targetSdkVersion="21" />
change the targetSdkVersion to the one currently installed on your system
Next, open the project.properties file and update
target=android-21
to your current SDK version
Finally, clean and re-build the project

Right Click on Project-> Select Android tools -> Select Fix Project Properties
This did the trick for me.

You need to click on the menu icon with the Android sitting in the grey box with a white arrow pointing down "Opens the Android SDK Manager".
or, from the command line, run:
%ANDROID_HOME%\tools\android sdk