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I can't uninstall Firefox.

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  • 39 have this problem
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  • Last reply by Norah

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I cannot uninstall Firefox. Evertime I open C:\Program Files\Mozilla Firefox\uninstall\helper.exe, a box appears and it says "C:\Program Files\Mozilla Firefox\uninstall\helper.exe is not a valid win32 applicartion.". Why is that?

This happened

A few times a week

User Agent

Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/533.4 (KHTML, like Gecko) Chrome/5.0.375.99 Safari/533.4

I cannot uninstall Firefox. Evertime I open C:\Program Files\Mozilla Firefox\uninstall\helper.exe, a box appears and it says "C:\Program Files\Mozilla Firefox\uninstall\helper.exe is not a valid win32 applicartion.". Why is that? == This happened == A few times a week == User Agent == Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/533.4 (KHTML, like Gecko) Chrome/5.0.375.99 Safari/533.4

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I fixed this by downloading and installing FireFox again from firefox.com firefox.com. It effectively "upgraded" my current version that originally failed on internal update.

It appears like it kinda half uninstalled when attempted the internal update, so maybe that is why it produced this error? I am not a firefox developer, so not absolutely sure, but re-download and install worked for me.