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What files does Firefox install on my computer?

I have malware on my computer. I can use the internet, but when trying to download software from actual software developers, most of the time Mozilla ends up blocking 100's of pop-ups, or they get through and I get routed to either a bogus anti-virus software message, or just random pages pop-up.

The problem also happens with Microsoft edge, and Internet explorer.

I looked through cmd prompt, and have found several "auto-run" or "installer" programs within Firefox and in other directories.

I'd like to just delete these from cmd prompt, but I know only some are harmful, and some are needed by Firefox to work.

Is there a list somewhere of what firefox installs and what is needed?

Or should I just uninstall all of them, and reinstall?

I have malware on my computer. I can use the internet, but when trying to download software from actual software developers, most of the time Mozilla ends up blocking 100's of pop-ups, or they get through and I get routed to either a bogus anti-virus software message, or just random pages pop-up. The problem also happens with Microsoft edge, and Internet explorer. I looked through cmd prompt, and have found several "auto-run" or "installer" programs within Firefox and in other directories. I'd like to just delete these from cmd prompt, but I know only some are harmful, and some are needed by Firefox to work. Is there a list somewhere of what firefox installs and what is needed? Or should I just uninstall all of them, and reinstall?

All Replies (3)

Could you try starting Windows in its "Safe Mode with Networking" mode to see whether you can safely download cleanup tools that way: https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode

Our support article lists numerous free programs that are very effective cleaners: Troubleshoot Firefox issues caused by malware.

Circling back to your question, it really wouldn't make sense to post a list of hundreds of files you'd have to compare and weed through. Once you can download a clean Firefox installer, then:

Clean Reinstall

We use this name, but it's not about removing your settings, it's about making sure the program files are clean (no inconsistent or alien code files). As described below, this process does not disturb your existing settings. It's not essential to uninstall Firefox, but you can if you like, saying No to any request about removing personal data.

It only takes a few minutes.

(A) Download a fresh installer for Firefox to a convenient location. You can choose between:

Regular version for Windows 7-10 https://www.mozilla.org/firefox/all/ Note: only runs Flash, no other legacy plugins "Windows" version is standard 32-bit version, which is generally recommended; to take advantage of more memory, you could switch to the 64-bit version, see: How to switch from 32-bit to 64-bit Firefox

Extended Support Release for Windows XP-10 https://www.mozilla.org/firefox/organizations/all/ Note: Windows (32-bit) runs legacy plugins that ran in Firefox 51; 64-bit runs Flash and Silverlight. (If anyone reading this is thinking of switching to the 64-bit version, see: How to switch from 32-bit to 64-bit Firefox)

(B) Exit out of Firefox (if applicable).

(C) Using Windows Explorer/My Computer, rename the program folder as follows:

64-bit Windows users with 32-bit Firefox: Rename

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\OldFirefox

Other Windows configurations: Rename

C:\Program Files\Mozilla Firefox

to

C:\Program Files\OldFirefox

(D) Run the installer you downloaded in step (A). It should automatically connect to your existing settings.

Note: Some less used files may exist only in that OldFirefox folder, so I suggest retaining them for a few days in case we need to go looking for something in there.

Any improvement?

Thank you.

I'm writing my thesis right now as well. When I get the first draft done, I'll sit down, do what you've suggested, and I'll let you know.

Thesis? Please keep backups! For example, if you have a Microsoft account or Google account, you can copy your documents to a OneDrive or Google Drive folder. You may want to create a folder for each day as you go so if you need to look back to an earlier version, you'll be able to do that.