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Unsupported kotlin version

My gradle build completes successfully, but I get:
WARNING: Unsupported Kotlin plugin version.
The `embedded-kotlin` and `kotlin-dsl` plugins rely on features of Kotlin `1.5.31` that
might work differently than in the requested version `1.6.10`.
All of my build.gradle.kts scripts refer to using version 1.5.31. The only association my project has with version 1.6.10 is that Android Studio has the Kotlin version 1.6.10 plugin added. If I try to disable that plugin, I get a message that several other plugins will be disabled. If I accept that, android studio crashes and will not start up again. It won't start up again even if you reinstall android studio again. The solution is to find the file named "disabled-plugins.txt" and delete that file. It's in your AppData folder and in a JetBrains subdirectory. It turns out that it's one or more of those other disabled plugins that prevents Android Studio from starting up again.
The question I have is how do I fix this version mismatch issue. I can't delete the plugin from Android Studio for the reasons I mentioned above. If I try to update my project to using version 1.6.10 I get literally 100's of unresolved dependencies. And it seems from opinionated investigation that 1.6.10 still have too many issues for general use.
By the way, when I look at the gradle window for the project I can see where the dependencies come from. Usually when I look at the gradle window I just see sub project folders that I can drill into for more information, but for this project, it has an additional folder name dependencies. I don't know how they get into my project. But when I look at their version numbers that's where the 1.6.10 mismatch happens.
So, I think I understand why the warning message is valid, I'm at a lost on what I need to do to correct this situation. For the moment, I'm just ignoring the warning, and so far I'm not finding any issues in proceeding that way. But that's means I'm proceeding, without an understanding of what's going on here! Sometimes that's okay and at other times that's a bad judgment The error message itself seems inverted. I would think that 1.6.10 is the embedded kotlin and kotlin-dsl since it an android studio plugin, but the error message seems to say it in the opposite way. So anyway, if someone can bring some clarity as to what's going on, and how I'm thinking wrongly about this problem would be greatly appreciated.

I'll accept the following as the answer to what's going on about the unsupported kotlin version:
https://github.com/gradle/gradle/issues/13020
So, for the moment, I'll go on like this is just a nuisance warning and ignore that.

What I just did was to re-create my Android Studio from a blank brand new project. I copied and pasted stuff from the previous project into the new project. I copied the source and build.script.kts files, so essentially everything is a copy of the disabandoned project. This new project didn't give me the WARNING message anymore. And in additional, I'm now able to upgrade my project to using kotlin 1.6.10, which I previously couldn't do because of the literally 100's of dependencies resolution issues. Whatever, that issue went away, and a lot of others things started working as expected once I recreated the project. I can't say what got my project into that weird state. Deleting the .gradle and .idea folders, wouldn't fix the problem. I didn't try deleting the JetBrains cache, I wish I would have tried that.

Intellij IDEA 14 - Package R does not exist

Well, I recognize that this has been asked before, but in browsing the other answers:
IntelliJ IDEA - Can't build anything, always get "package R does not exist"
Error: java: package R does not exist
etc.
none of the solutions work.
This is for a project that was building fine until at least the last couple days, so whatever is causing the problem must be new.
Symptoms:
Attempting to to a Build > Rebuild Project fails. I see the step for compiling generates sources go by in the status bar, but the next compilation step fails with the dreaded "java: package R does not exist."
R is found just fine in the IDE, so only compilation fails, suggesting there is a problem with the compilation of the generated sources. This seems borne out by the fact that in the out/production/[module] directory, only some resource files show up, no compiled classes, nothing in the "generated" sbupackage, a no apk file.
Interestingly, when I connect my phone to the computer and try running the application on the device, new changes are picked up, so something is being successfully built somewhere.
Things I've tried:
Per the other threads I've tried:
Doing a full rebuild.
Restarting IntelliJ (including with invalidating caches)
Restarting the computer.
Checking that the gen package is included under sources.
Checking for any Excludes (there are none)
Deleting the stub R file and forcing IntelliJ to regenerate it (which it does promptly)
Confirming that there is an Android facet on the module.
Double-checking that the manifest xml file has not changed and that the referenced activity is correct.
Checked that exclude output path is not checked (it's greyed as I'm inheriting from the project compile path, but I tried switching and manually unchecking it... no luck).
The only recent changes in xml were:
A new item in a menu file. I tried removing it to see if somehow that was an issue even though there were no errors reported, but the problem persisted.
I moved a View class to a subpackage of its prior package. That View class is referenced once in a layout xml and I confirmed that the xml was updated with the new package name.
So at this point I'm out of ideas. Sorry to rehash a somewhat common question.

I have the same problem and it definitely related to last update of the IDE. My version is IU-139.1117.1
Before the update Build -> 'Rebuild Project' was working ok in a windows and a mac installation of the IDE. I updated windows first and 'Rebuild Project' shows the error 'Package R does not exist' even for a new Android project. Same error apeared in mac installation imediately after the update. 'Make project', 'Make module' and 'Compile' commands on the Build menu are all working ok with no error only 'Rebuild project' raises the error.
For a new Gradle Android project everything works ok. It seems something is wrong with last update.

It is reported issue in IDEA 14.0.3 (http://youtrack.jetbrains.com/issue/IDEA-135234).
You can try to Compile Module (Ctrl-Shift-F9) for the module that contains missing R file. It works for me (but I have to do this every time i add/remove items in resources).

don't use Rebuild Project, use Make Project and refresh your project,maybe you should try it a few more times.

Try File | Invalidate Caches. This is solve my problem.

If you cannot wait for a officially stable build, install IDEA EAP 14.0.4 (IntelliJ IDEA 14.0.4 EAP build 139.1408, released on February 20th, 2015) from https://confluence.jetbrains.com/display/IDEADEV/IDEA+14+EAP
I've just solved all issues and rebuild project works again.

Solved with the 14.1 update of intelliJ IDEA, available now.

I had the same issue on a Windows 7 box today with a Java 7 Gradle project, using IntelliJ 14.1.5.
The problem was that somehow the classpath was "too long", but IntelliJ gave me only those strange "java: package foo does not exist" compile error's.
The usual tricks (see also above) did not help.
The workaround was to shorten the classpath a bit, in my case setting GRADLE_USER_HOME to c:/.gradle (was before c:/users/myusername/.gradle). After resyncing the gradle project everything worked fine.
The problem was therefor obviously IMO some kind of windows filesystem path length restriction.

Could not find BaseGameUtils.apk

For the last 2 days I've been trying to simply get Google play game services Integrated into my game. I've followed the instructions here...
https://github.com/playgameservices/android-basic-samples/blob/master/README.md
...many many times. I have been trying to get it to build with Gradle but for now, I'll just focus on Eclipse building until that works. I've imported BaseGameUtils project into my workspace as an Android library project. My game android project has two Android library dependencies: google-play-services_lib and BaseGameUtils. Everything in Eclipse is showing without any errors. When I build and run on a real device, I see an error that says -
[2014-10-27 20:39:25 - BaseGameUtils] Could not find BaseGameUtils.apk!
I don't know why it's even looking for BaseGameUtils.apk since it should be an Android library. That said, I'm not sure how an Android library is really handled so maybe it should be a .apk. In any case, I couldn't find any information on this bug and the error message doesn't give me much to work with. I've tried adjusting things in the Build Path but no luck. I did have to remove some redundant dependencies in my Build Path earlier since I was getting some kind of duplicate DEX error but I'm not sure that's related in any way to this. I am desperate for help, anyone have any idea?

Can you try this? It has to do with conflicting methods of specifying that a project is a library.
I found the source of the problem!
It turns out that "with the new library feature, you don't specify the
Android projects you depend on in the Java Build Path section of the
Properties. You do it in the Android section of the Properties".
So all I had to do is go the Application Project's Properties, hit the
Projects tab, select my own library project and click the Remove
button. That's it. No more problem.
In Eclipse Java EE select the project Properties, then select Project
References, then check the FacebookSDK (see screen capture)
From: Android Eclipse - Could not find *.apk
If that doesn't help, you may want to double check that you selected "Is Library" in BaseGameUtils.
Also, when you hit "Run" in Eclipse, are you running your application and not BaseGameUtils?

Please would you check that BaseGameUtils has "is library" checked and that your application project DOES NOT have "is library" checked.
If this is correct, then please would you review the following in detail (especially as regards checking and unchecking "is library" ) :
Android Eclipse - Could not find *.apk
I presume that the DEX error related to two or more versions of the same lib. What is the specific GameHelper error ?
As a general point, I find it productive to get a sample project working first to ensure that I have got the environment working correctly before I start integrating game services into my own projects. If you have been changing the build path then it may be quicker to start from scratch and get a sample working. I have followed those instructions in the past and they are accurate.

unable to instantiate application - ClassNotFoundException

EDIT: This problem has not already been resolved in the other suggested SO question
I had a fully working app on the market for over a year, with very few crash reports. Then recently I changed my app into a library, so that it could be included within multiple different "wrapper" projects. This was so that I could easily make different version - free, paid, non-google markets, with/without in-app purchasing etc etc.
The new "library+wrapper" app appeared to work fine. I could run it multiple times, without error. But then a day later (when presumably the OS had closed some or all of the app's activities) I tried to run it and it reported
Unable to instantiate application com.mycompany.mygamelibrary.MyGameApplicationClass: java.lang.ClassNotFoundException: com.mycompany.mygamelibrary.MyGameApplicationClass
The class it failed to find is the first class that runs when the program starts up, MyGameApplicationClass - which extends Application. This class is part of the library.
I suspect something goofy in one of the two manifest files.
The manifest of the wrapper project contains the lines...
<application android:icon="#drawable/mygame_icon"
android:screenOrientation="portrait" android:label="My Game Name"
android:name="com.mycompany.mygamelibrary.MyGameApplicationClass">
Any ideas what could have gone wrong?
EDIT: The library was referenced "the correct way" as defined by yorkw's answer to this SO question.
EDIT: I can not repeat the crash at the moment :-( I don't know what it is the OS does when the app is not used for a day or two.

There are two possibilities. Either you, like me, have a spelling error in your manifest file. Have a co-worker or friend read it to make sure the name is correct. Or you have not referenced the project correctly.
The official document describes how to properly link projects in its documentation.
Why it would first seem to work and later stop working is a bit of a mystery. However, I guess that the VM might still have had the necessary references ready to resolve the classes in the library just fine. A restart of the VM removed all those references and trying to resolve them was unsuccessful.
Update: Regarding the edits in the OP: As you confirm that you have correctly referenced the other project, you can check if the project is included in APK, just to be sure. You can rename and open an APK as any other archive (.rar works fine for me). Sometimes, it happened to me, the project is not correctly included in the APK. A cleaning of your workspace usually remedies the problem and so could a restart of your IDE depending on what you are using. To manually conduct a clean in Eclipse for example, use Project->Clean... or try Android Tools->Fix Project Properties by right-clicking on your project.
As you seem to also have fixed the problem by restarting your device, it could be that the libraries were linked incorrectly. A problem that I have never seen myself but as a very common quote says: "Have you tried turning it off and on again?".

For Android Studio:
Build --> Clean Project
Fixed issue.

Have you tried to make a new subclass of MyGameApplicationClass in your 'main' project and set it in the manifest as Application class?

I had a slew of bugs with Android Studio 3.0 Canary 4 and the way I fixed them was by editing the AndroidManifest.xml by adding in some jibberish to the application name. Then, I clicked build. Obviously, a whole mess of new error messages appeared. I changed the name back to what it should be, built the app, and it just ran.
Sometimes, I just don't know...
EDIT: Just ran into this issue on Android Studio 3.0 Canary 4 on my laptop when switching over. I again went through the same process of changing AndroidManifest.xml file to contain a typo, building, and changing back. That didn't work.
I then noticed that instant run was still enabled. Going into settings (by clicking command + , (comma key)) and typing "instant run", I was able to disable instant run, built the app, and the error of class not found went away.
Summary of Steps to Fix [FOR ME]
Invalidate cache / restart
Clean the project
Manually delete the build folder (need to be in project view for this one)
Make an intentionally errant edit to your AndroidManifest.xml file, build the app, observe the errors, remove the errant edit and build again
Disable instant run
Again, I don't mean to insinuate that this will fix everyone's error, but I have now used some combination of these steps on two different machines (MacOS Sierra) and it has been resolved for me. Hope it helps.

In my case, application id and package were mismatched. This should be same as presented in following images...
AndroidManifest.xml
app/build.gradle
In this case you can see, applicationId and package both are same that is com.mycompany.mygamelibrary

May be its a Build Path Configuration problem.I did the following to solve the issue.
1.Right click on your project and go to Java Build Path.
2.Click on Order and Export tab.
3.Check Android Private Libraries and other 3rd part libraries if you have added.
4.Press ok and clean the project.
I hope it will solve the issue.

Once I had the same error message, but maybe the cause isn't the same.
I did a code and worked for a while, then I wanted to improve it and got the same error and I couldn't run it.
I could fix the problem with
the correct Build Path order (as I can see you've already did this)
I check on the Order and Export tab the android-suppor-v4.jar
and the key was the Android SDK Managert->Upgrade everything and (next) Eclipse->Help->Check for updates.
After I upgraded to the latest android plugin and SDK my app compiled and ran again.
I hope this will help you!

I'm not very sure about this but it might be that your system's debug.keystore license validity has expired as it is valid for only 365 days. You just need to delete the debug.keystore from your computer. The debug.keystore will be generated automatically by Eclipse when you compile your Android App.

Same message seen ... this time it turned out to be different output folders for MyApp/gen and MyApp/src in the Build Path (caused by Maven integration).
Unchecking "Allow output folders for source folders" solved the problem.

I had this issue in an Android application that needed an Application class which was created in wrong path inside the Android Studio project. When I moved the class file to the correct package, it was fixed.

This all Process work for me to solve application class Exception.
Step 1: Open Run(window+R) Search -> Prefetch Remove all file (Some file not Delete)
Step 2: Open Run(window+R) Search -> %temp% Remove all file (Some File not Delete)
Step 3: Open Android Studio -> Build -> Clean Project
OR
Select File > Invalidate Caches / Restart > Invalidate and Restart from Android Studio toolbar.
OR
Close and reopen Android project.
OR
Restart System

I ran into this issue several times and both times it seemed to be caused by some instant run feature.
In my case, deleting the application from the device and then installing it from Android Studio again resolved the issue.

I ran into this problem today. The project runs well for over a year but today it reports this issue, and cannot debug on my testing device.
I fixed it by updating to latest gradle version. Hope this can solve your problem.

Conversion to Dalvik format failed with error 1 with javax/net/SocketFactory.class

Encounter this problem when trying to Build Project getting such output in console:
[2010-07-19 23:29:23 - myProject]
trouble processing "javax/net/SocketFactory.class":
[2010-07-19 23:29:23 - myProject]
Attempt to include a core VM class in something other than a core library.
It is likely that you have attempted to include the core library from a desktop
virtual machine into an application, which will most assuredly not work. If
you really intend to build a core library -- which is only appropriate as
part of creating a full virtual machine binary, as opposed to compiling an
application -- then use the "--core-library" option to suppress this error
message. If you go ahead and use "--core-library" but are in fact building
an application, then please be aware that your build will still fail at some
point; you will simply be denied the pleasure of reading this helpful error
message.
[2010-07-19 23:29:23 - myProject] 1 error; aborting
[2010-07-19 23:29:23 - myProject] Conversion to Dalvik format failed with error 1
I was looking for my project to use the package javax, not found, clean all also does not help. what I am doing wrong?
Update
Sorry guys, but I could not find good fix for that, I want to emphasize the fact, that i dont use SocketFactory class in my project at all! source code was not changed before this problem, and that's why i think that problem in eclipse or adt or something else, BUT if i use ant(generated by sdk) to build this project there is no problem!!!
I solve this problem by removing Eclipse, Android SDK, Eclipse workspace, and just reinstall them, after this all works fine for now.
Hope this will help someone.

I had the same problem..
This worked for me
project-->properties->java build path->libraries-> remove all including android jars
now go the project browser, right click on the project you are working on,
then android tools---> fix project properties...
do a clean and then build...

I solved the problem (at least for me).
Here's what I did:
Go to Project » Properties » Java Build Path » Libraries
Remove all except the "Android X.Y" click OK.
Go to Project » Clean » Clean projects selected below » select your project and click OK.
That did the trick for me.
Hope it works for you as well
Update: well actually I might have to retract my opinion.. the actions removed the error messages but now I am missing certain classes and methods... arggghhhh

I just restarted Eclipse, and the error didn't appear anymore!

I had the same problem,and solved it as follows:
First clean all jars; (This problem must because your some jars)
Delete the project;
Reimport project;
Make sure your sdk is right, and project select one sdk version;
(This is my issue to solve the problem) Right click your project, and select "build-path", next select "add Librarys", and add your private jars;
clean-build, the problem has fixed;

I just had the same problem and I tried all of the solutions listed here with no success (I was starting to get annoyed). Then I removed the project from the workspace and then imported it again, and there were no problems!

This happened to me this way,
I have a quite an old project which I had to start working again today. I use 'Universal Image Downloader' library for basically every project where I have to deal with lots of images. So in this old project I had the source files of 'Universal Image Downloader' included to it's 'src' path. Back then I was a newbie and slowly I started developing my own library which could handle every day simple Android development tasks very easily. Obviously I included the 'Universal Image Downloader' to this.
After dusting off the old project today the first thing I did was to reference my library to speed up the development process but as I was trying to debug I ran into the "Conversion to Dalvik format failed with error 1" over and over again. First I thought it was the support library but even after clearing all libraries and adding only mine and doing a quick 'Fix project properties' I still got it. After trying various solutions I noticed this in the console "java.lang.IllegalArgumentException: already added: Lcom/nostra13/universalimageloader/cache/disc/BaseDiscCache;"
It was as simple as that... I'm trying to compile a class which has already been compiled.
Solution : I just simply removed all the class files I got from 'Universal Image Downloader' library from the 'src' directory. Since my library references "Universal Image Downloader" library the old project started working just fine.

Hit same problem shown on your log when trying to run an example project which was imported into eclipse.
Additional Info: in eclipse's Problems View I see the following error:
"The project cannot be built until build path errors are resolved"
In my case the imported project find the libraries just right(by just right I mean I can see the external path to each of the android libs in this case 2 libs, android.jar and maps.jar). So no shuffling of libs in my case, but might be your problem.
I followed Spock's suggestion of cleaning the project which I had to clean multiple times until it somehow resolve its issues. After, issue was solved I had to specify an AVD for the project to run and soon after was up and running on the emulator. Also, note that my eclipse is set up to Build Automatically.
In my case I'm not missing any class files or anything after the clean as the build is properly generating them.
Regards!

I was getting the same error. My problem was that i had an android device hooked up to debug with. As soon as I unplugged it I was able to export.

The answer I found was checking the source and library build path in the project's properties. Most likely there will be a duplicate as in something being referenced in both the source and library tabs. So delete the extra in the source tab and then clean the project and you should be good to go.

Either:
javax.net.SocketLibrary is in your source code, or
javax.net.SocketLibrary is included in a JAR file in your project

Under certain conditions it gets its knickers in a twist and the best fix I've found is to remove referenced jars, clean, add them back in and then compile again.
I believe the error can be caused by including the same classes twice.
This error will also occur (and you won't be able to get rid of it by cleaning) when using classes that are not part of the Android environment.

To summarise the information in the link bimbim.in provided (well my understanding when I glanced over it)
The Android Davik VM tries to compile the jars but finds some stuff that it can't compile to .dex files
so
Just create a "lib" directory in the root of the project (where the src, bin res directories are) and add them to the build path. Project Properties... Java Build Path... Libraries.. Add JARs..

I could resolve this issue by creating a new project, looks like the some project settings were creating this issue and could not really find the root cause for that. But, dumping the existing source code onto the new project resovled this issue. If anyone has found the root cause for this problem pls do let me know.

I had the same problem and solved it as follows:
- Go to Project/Properties/Java Build Path/Libraries and remove all JARs except Android
- Do a project clean
- Add the JARs again as External JARs (first time I added them internally, so that might be the problem)
After that the error was gone.

I solved the problem by updating available packages in the Android SDK et AVD manager. No need to remove Eclipse.

Whenever the Project is having the ambitious data. This problem is caused. May be android can't able to find which one choose.

From what I understand, this same cryptic error could be caused from a wide variety of reasons. I've got "Conversion to Dalvik format failed with error 1" error too. In my case the problem was that for some reason Project -> Properties -> Java Compiler was not set to "Enable project specific settings" with proper Java 1.5 settings, but was left to defaults instead (1.6 in my case). Debug, build and test on devices/emulators worked fine, but export always failed with the above error message.
If unsure about the proper settings, create the same project on some alternative location and just copy all needed files from the old project into the new one. This fixed the issue for me.
The next problem with the same error message came from using proguard. Updating to the latest version by replacing the one that came with android sdk, fixed that.
Hope this helps

My problem was having a jar file in my src folder. Removing jars from the build path works, but only if you don't need the jar in question. For people who need the jar in question, make sure that your jar file is not in the project folder (maybe just src subtree, but I would keep it separate to test). Put it on your desktop or something and try the "Add external jar.." option. Be sure to remove the jar from the project filesystem before adding another external. Having both is what causes the problem.

I have done it as the instruction of the first answer and it works.(Linux)
I think the problem may caused by SDK or ADT updates.
I do have to clear all the lib in Java Building path and then use android tools to fix the project. After cleaning and rebuild, it works as before.