android-discuss, Help!!! Unknown Error - java.lang.NullPointerException :: Android Packaging Problem

 I'm getting this crazy error on multiple projects, even when I revert
back to prior versions that compiled just fine.

Unknown Error - java.lang.NullPointerException Android Packaging
Problem
Path is blank
Location is Unknown.

I've tried:

1 - Project -> Clean -> All
2 - Deleting .metadata folder
3 - reimporting projects into the eclipse
4 - reverting my projects back to prior working versions using git

Please please please help... I just can't get anything to compile now,
and I've searched for solutions here and on eclipse forums.

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 This sounds more like a problem with your dev system than with your
code. Try re-installing Eclipse and the SDK. Export all your Eclipse
preferences first, of course (File->Export->General->Preferences).

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 Finally figured it out.

==Short version

My .project file was corrupted and I needed to manually update linked
library locations.  Since the .project file was pointing to the wrong
place, a null pointer exception was thrown.

==Long Version

For some reason, the GUI and project settings were disconnected form
one another.  When I went into project settings, my libraries looked
to be correctly linked and properly found in the build path.

However, when going into the .project file using a text editor, there
were straggler linked libraries.  (ie multiple versions of the same
library, pointing to two different locations)

Most likely user error on my part, but something to keep in mind if
you get the "unknown packaging error".

Thanks for the suggestion Bret... I did reinstall everything, but the
problem persisted, as per the fix above.

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