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R cannot be resolved, tried everything

I have really tried everything imaginable!
Okay, I know everyone says that they have "tried everything" and I know that there are a million and one "R cannot be resolved" questions and tutorials. However, I have done them all, literally! I have cleaned and built, deleted my project and reimported it, checked for capital letters in my resources, checked my XML in general for errors, checked my package name in the manifest, I have the correct build tools, package tools, and platform tools, I have checked my imports on my classes, I have made sure the build path has the correct boxes checked (Android version #), and I have changed the order of the build so that /src is last and still nothing!
The problem came about after I did an update to the SDK and ADT; however, like I said earlier, I made sure to have the correct packages. I also tried adding a values-es folder to my project after the update, but I had made a backup up of my entire project before the issue, so when it lit up like a Christmas Tree with errors I just reverted back to the original.
tl;dr
I have literally tried every answer and tutorial on SO and elsewhere and still have an issue with R cannot be resolved. I believe it may be linked to the SDK and ADT update but Im not sure.
Edit 1
What I've tried
1 Tech Republic Help (all of the suggestions except the last one)
2 SO 1
3 All of the answers in this SO thread
4 This SO thread and the dozens of other similar ones that don't need listing
Please help, I have worked for hours getting updates put in place only to not be able to publish them. This is an infuriating problem!
Edit 2
Package and import pictures

I found this happening to me with a broken layout. No need to be worry. I am trying my best to giving you the solution
Solution
Make sure that anything the R. links to is not broken. Fix all errors in your XML files. If anything in the ADKs are broken, R will not regenerate.
If you somehow hit something and created import android.R in your activity, remove it. Run Project -> Clean. This will delete and regenerate R and BuildConfig.
Make sure Project -> Build Automatically is ticked. If not, build it manually via Menu -> Project -> Build Project .
Wait a few seconds for the errors to disappear.
If it doesn't work, delete everything inside the /gen/ folder
If it still doesn't work, try right-clicking your project -> Android Tools -> Fix Project Properties.
Check your *.properties files (in the root folder of your app folder) and make sure that the links in there are not broken.
Right-click your project > properties > Android.
Look at the Project Build Target and Library sections on the right side of the page. Your Build Target should match the target in your AndroidManifest.xml. So if it's set to target 17 in AndroidManifest, make sure that the Target Name is Android 4.2. If your Library has an X under the reference, remove and re-add the library until there's a green tick. This might happen if you've moved a few files and folders around.
What to do if R doesn't regenerate
This usually happens when you have a broken xml file.
Check errors inside your XML files, mainly within the /res/ folder
Common places are /layout/ and /values/ especially if you've changed one of them recently
Check AndroidManifest.xml, I find that often I change a string, and forget to change the string name from AndroidManifest.xml.
Check that Android SDK Build-tools is installed. Window->Android SDK Manager->Tools->Android SDK Build-tools
Make sure when you update the Android SDK Tools, you also update the Android SDK Platform-tools and Android ASK Build-tools. Build fails silently if they don't match.
If you can't find the issue, right click /gen/ -> Restore from local history... -> tick R.java -> click Restore. This doesn't solve the problem, but it will clear out the extra errors to make the problem easier to find.
Hope it will help you. :)

There are lots of reasons for this kind of problem, that makes it frustrating.
But since you got this after an update, I suggest you follow this discussion. which suggests to install new Android SDK Build Tools from Android SDK Manager.

As a last resort, you can create a new project and piece it together file by file with your existing code (Running it, of course, at every possible instance[change]) and wait for the error to show itself.
For what it's worth, these are usually xml errors in my experience.
Good Luck

"R cannot be resolved" may have wrong build path or libraries import

I know this question has been many times but trust me I have checked all. Most of the question suggests to remove import android.R , remove any error in the xml file, checking name of the files (no capital letters) then rebuild and clean the project or restart eclipse. I have tried all but none solved the problem.
The problem occured when i cleaned all the projects. Now all the projects are showing that error. Since all the project were running perfectly before i cleaned projects, there is no possibility that all of the sudden the layouts or the file names of all the projects have error in them.
Also there is no file in gen folder. As far as i can understand there is something wrong with the build path or preferences can anyne point me in a correct direction? !

Make sure you installed the Android build tool form sdk manager
project right click properties-> Java BuildPath select Library and add android-support.jar the follow these step.
Go to Project->Properties->Java Build Path than select Order and export tab. Set android-support .jar library checked and up it into top of the list. And clean and rebuild..It works for most of the cases

Check the answer here and the thread here. Check if your layouts contain any errors (this has to be done manually or automatically only with Android Studio). Search for incorrectly closed tags like <string> - </string>.
EDIT (taken from this thread):
Cleaning a project removes all auto-generated files. Building the
project it should automatically create them. When you Clean a project,
there's an option to start a build immediately after clean up.
Here's a few things you can try (did the same procedure after manually
deleting the "gen" directory.
After you have deleted the gen directory, go to Project > Clean ...
You should have errors indicating that R cannot be resolved to a variable. Right click on your project from the Package Explorer and
select Build Project. Be sure Build Automatically option is turned off
(uncheck in Project > Build Automatically).
Errors regarding R should have now disappeared. Now, perform a Project Clean once again. All errors should be gone.

Android: In Eclipse project missing Google APIs?

I have a work space with many projects. One of them is suddenly missing the Google APIs libraries even though it is clearly checked. the properties file lists it correctly.
How do I get Eclipse to add these to this one project?

once i had problem like this : i tried many but can't find and positive solution.(1)
- make new project with required target and move src, res, ref and manifest to this new project.(2)- Just try remove auto build option from project menu and then delete gen folder and just build project and then clean & build project.

This often works for me:
Select another build target and click 'Apply'. When the update is finished I select the previous build target and then 'Apply' again.
Remove 'bin' and 'gen' directories from my project and select the clean option in the project menu.

Eclipse Android project

I have a problem I can't seem to get around. I've created a project in Eclipse (I recreated it from another project that I thought was corrupted). There are no visible errors in any of the files, including the .xml files. However, the project root [project name] itself has an error (red 'x') and so I can't run it.
On a side note, in the default properties file the line:
target=android-4 is underlined in red with the note that 'android' is not spelled correctly. I have not altered this file since it was generated.
Any clues? Target is 1.6, sdk 4. And I'm new at this :)

You may have already tried this unsuccessfully, but if not, you might want to try the Android Tools > Fix Project Properties action from the context menu of the project root.

Eclipse also thinks android-4 is misspelled in my default.properties, so I doubt that is the cause of your build problem.
Does the Problems view describe any issues? (Window->Show View->Problems)
You could also try cleaning the project in eclipse. Project->Clean..

if the error message you get is
The project cannot be built until the build path errors are resolved.
this might help:
Open the Project -> Properties
Select Java Build Path -> Libraries
Add any new library (to be deleted later) -> OK
Wait for the workspace to refresh or force a refresh
The error should go away
Remove the dummy library

You can stop the spelling error by adding that word to a user dictionary, but a spelling error wouldn't prevent a run.

Eclipse - HelloWorld - Android error?

I created a Hello world app but get this strange error:
The project cannot be built until the build path errors are resolved
I haven't changed the project, jut created it and tried to run it.

to avoid that annoying problem i have 3 solutions that worked for me.
Solution 1)
delete your generated R.java file
inside your gen/ folder
Solution 2)
a)Delete your project from Eclipse
(i said ONLY from Eclipse, uncheck option: Delete project
contents on disk)
b) import your project to Eclipse:
file > Import > Existing Projects into
Workspace (Look for your project
previously deleted from Eclipse) >
Finish.
Solution 3)
make Solution 1 then Solution 2

It is either a spurious message you can solve by forcing Eclipse to recompute its library paths
I found the resolution for this at Scott D. Strader's blog.
To summarize the solution I only needed to add a library to my project and then remove it to force Eclipse to perform the necessary actions to resolve the problem. I would post the detailed steps here but I don't want to steal his content.
The resolution was to force a resave of the selected projects (and their .classpath files):
Open the project properties
Select Java Build Path > Libraries
Add a new, arbitrary library (to be deleted later) > OK
Wait for the workspace to refresh (or force a refresh of the project)
The error(s) will go away
Remove the dummy library
Note: as the OP mentions, a simple restart of the IDE can be enough.
Or you actually miss one critical library like a JRE library:
I needed to add the JRE library to the project for it to run. Not sure if this was due to the updated version or something else…. Any way this fixed the issue:
Project > Properties
Java Build Path
Libraries tab
Click add library
Select JRE System Library
Next
Finish

Sounds like you are missing an import or a jar. In your project in the project explorer there should be a red x on the file icon that contains the error.

In addition to the listed answers, there is one other scenario I've seen this error appear when using the sample projects included with the Android SDK. For some reason, the generated R.java file can be invalid or corrupt. You can get around it by expanding the "gen" folder in the Package Explorer and deleting the R.java file. It will immediately get regenerated and the error goes away.

Right click on your project, choose "Build Path", "Configure Build Path" -> and choose Android 2.2, or that target you specified when you created your project

I have had similar issues. for me simply closing the emulator and re-running the project works