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Firefox stopped working properly, it says it cannot initialize the applications security component...

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Firefox starts with this: Could not initialize the application's security component. The most likely cause is problems with files in your application's profile directory. Please check that this directory has no read/write restrictions and your hard disk is not full or close to full. It is recommended that you exit the application and fix the problem. If you continue to use this session, you might see incorrect application behaviour when accessing security features.

it then opens and will not let me click anything, just opens the homepage and stops, tried reinstalling and it still doesn't work.

Firefox starts with this: Could not initialize the application's security component. The most likely cause is problems with files in your application's profile directory. Please check that this directory has no read/write restrictions and your hard disk is not full or close to full. It is recommended that you exit the application and fix the problem. If you continue to use this session, you might see incorrect application behaviour when accessing security features. it then opens and will not let me click anything, just opens the homepage and stops, tried reinstalling and it still doesn't work.

All Replies (4)

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See:

Rename secmod.db (secmod.db.old) in the Profile Folder in case there is a problem with the file.
You may have to rename cert8.db (cert8.db.old) as well.
Firefox will create new files.

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This appears to be a new variation on an old theme. None of the old solutions for the similar "Could not initialize the browser's security component" work for this. Note the slightly different message "Could not initialize the application's security component".

As the OP has stated, reinstall does nothing, Firefox is DOA.

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Create a new profile as a test to check if your current profile is causing the problems.

See Basic Troubleshooting: Make a new profile:

There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.

If that new profile works then you can transfer some files from the old profile to that new profile (be careful not to copy corrupted files)

See:

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Tried a new profile while attempting to follow the previous solutions. Also tried starting in "safe mode". Just installed 6.0, so assuming it's related.