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My Firefox is corrupt. I uninstalled & reinstalled it after running malware program but it is still corrupted.

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  • Last reply by John99

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A folder appeared on my desktop, out of nowhere, called 'OLD FIREFOX DATA'. Whenever I do a fresh reinstall, pages are still distorted. What can I do? I suspect that something in that folder is corrupt & being used during these reinstalls but I don't dare to delete anything in the folder.

A folder appeared on my desktop, out of nowhere, called 'OLD FIREFOX DATA'. Whenever I do a fresh reinstall, pages are still distorted. What can I do? I suspect that something in that folder is corrupt & being used during these reinstalls but I don't dare to delete anything in the folder.

Chosen solution

Please leave that folder alone for now. It should not be having any effect on Firefox, but could come in handy later.

I do not personally use the Firefox reset feature, but that does copy the old profile folder to the Desktop, and it is likely that is what happened. Did you do a reset recently ?

You have quite a few plugins listed, but did not list the extensions when you posted the question, or maybe after a reset you no longer have any. The reset does nothing to disable or remove plugins.

The reset or a standard reinstall also does not clean out the programs folder.

Run scans with multiple and up-to-date tools. Hopefully that will detect and removed something that has been missed. I would not suggest you try any manual hacks or edits of the Windows registry. (Once rogue files are removed any residual registry entry will not normally do any harm.)

Please post back again after you have done the scans. Say what scans you did and what the results were. - - - - - You can try these free programs to scan for malware, which work with your existing antivirus software:

You need to use multiple and up-to-date tools as they will not all pick up the same things.

Microsoft Security Essentials is a good FREE permanent antivirus for Windows 7/Vista/XP if you don't already have one.


Further information can be found in the Troubleshoot Firefox issues caused by malware article.

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Chosen Solution

Please leave that folder alone for now. It should not be having any effect on Firefox, but could come in handy later.

I do not personally use the Firefox reset feature, but that does copy the old profile folder to the Desktop, and it is likely that is what happened. Did you do a reset recently ?

You have quite a few plugins listed, but did not list the extensions when you posted the question, or maybe after a reset you no longer have any. The reset does nothing to disable or remove plugins.

The reset or a standard reinstall also does not clean out the programs folder.

Run scans with multiple and up-to-date tools. Hopefully that will detect and removed something that has been missed. I would not suggest you try any manual hacks or edits of the Windows registry. (Once rogue files are removed any residual registry entry will not normally do any harm.)

Please post back again after you have done the scans. Say what scans you did and what the results were. - - - - - You can try these free programs to scan for malware, which work with your existing antivirus software:

You need to use multiple and up-to-date tools as they will not all pick up the same things.

Microsoft Security Essentials is a good FREE permanent antivirus for Windows 7/Vista/XP if you don't already have one.


Further information can be found in the Troubleshoot Firefox issues caused by malware article.