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This comes up a lot, but I can't seem to fix it with the solutions listed elsewhere.

I have an unmet dependency from libnspr4.

I have done;

sudo apt-get clean
sudo apt-get autoremove
sudo apt-get update
sudo apt-get install -f

I have changed the server in software sources.

I am not sure I want to remove the package as when I do a dry run it seems to have many many things dependent on it.

I now have 36 packages showing as not upgraded when I do sudo apt-get install -f

I am becoming reluctant to keep poking around in case I break something.

Help greatly appreciated.

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Give us the exact error message. We can't solve without that. – jokerdino Aug 14 '12 at 13:40

This is a problem related to a recent stable release update in Ubuntu 12.04. We know that it's affecting a large number of users, according to the statistics on; but we have not yet been able to reproduce the problem ourselves so can't propose a solution. Please file a bug report by running 'ubuntu-bug libnspr4' from the affected system, and attach the output of this command:

sudo apt-get -oDebug::pkgProblemResolver=true install -f

(There will be a lot of output; you will want to redirect it to a file with '> logfile 2>&1'.)

share|improve this answer
Hi, great thanks.Bug report – Pete Aug 14 '12 at 23:59
There wasn't much output from the second command, so I just pasted it in. – Pete Aug 14 '12 at 23:59
In case you're not watching the bug, I've updated it with a few more debug output requests. Please do answer "no", if at any point it looks like it's about to actually usefully install packages, since we'd really like to fix this for everyone, not just work around it. ;) – infinity Aug 15 '12 at 0:19
Note that an updated libnspr4 package is now available. You should be able to upgrade your system by enabling 'Pre-released updates' in the 'Updates' tab of Software Sources. If you do this, your feedback on the bug is appreciated. – slangasek Aug 16 '12 at 4:26

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