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4.01 is a disaster; cant open tools/addons; wont restart in safe mode, toolbars missing when opening or moving to a new window.

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Subject line covers most of the question. Version 4.0 worked fine. I've uninstalled and reinstalled 4.01. No change. Tools, Addons doesnt reveal addons. New window opens with some toolbars missing and a blank page.

Using tabmix plus; maybe that's an issue? Using Default theme. But these were fine in 4.0

How can I revert to version 4.0? or the last release of 3?
Subject line covers most of the question. Version 4.0 worked fine. I've uninstalled and reinstalled 4.01. No change. Tools, Addons doesnt reveal addons. New window opens with some toolbars missing and a blank page. Using tabmix plus; maybe that's an issue? Using Default theme. But these were fine in 4.0 How can I revert to version 4.0? or the last release of 3?

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

See:

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

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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Thanks for taking the trouble to reply. I'll try this and post back with the results. Peter

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Hi, the solution worked fine, thanks. I used Mozbackup 1.5.1 to create a backup, backed up all files, and restored them all to a new profile. The problem was repeated.

Using Mozbackup again I restored to another new profile, and backed up everything except the "unknown files" (all deselected). That worked. I was able to open add ons and found an addon incompatible so I disabled it. All is well.

Thanks again, much appreciated.

Peter

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Please click the Helpful button next to the answer that solved your Firefox support issue, when you are logged in, so this thread gets marked as Solved to help other users who may have this same problem.

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Ok, will do that. One nagging problem still occurs with my paid Roboform toolbar when moving a tab with TabMixPlus to a new window. The toolbar appears but doesnt expand. Closing and reopening this toolbar solves the problem. I suspect it to be bug in TabMixPlus or maybe Colourful Tabs or Showcase. I can live with it for now.

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I had this problem as well - it was caused by a complex session with multiple tab groups, some of which needed authentication. I made a copy of my Profile and then deleted the session files, and Firefox came right up.

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Glad to hear you got sorted. I'm a heavy window/tab user too and use session manager to keep track of multiple sessions. It was fine before the upgrade though so in future I'll be sure to keep of copy of the previous version on file so I can roll back the clocks and start over if needs be.

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The issue is not how to correct a profile; but when 4.02 will come out to fix the problems that 4.01 has caused. Even a blank new profile (in 4.01), won't allow me to see online videos or play Facebook games. But 4.00 is fine.

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Sorry to hear about that! Have you checked to see if you have the latest version of Adobe Flash Player installed? If you have, then you could try downloading Adobe's Flash uninstaller from their website and then reinstalling the latest Flash. I dont know if that is the cause of your problem, but worth a try.

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An hour of updates, profile manipulation & other crap; I just came back to 3.6 and it's all fine again. 4.00 was fine, too - but I'm not going there again until it's more stable.