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your latest update just crashed my desktop computer. It is an older computer with NOrton and now I am unable to open, says unable to open runtime.

Rfranc
Rfranc
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Your latest update crashed my desktop computer. I've had Mozilla for a few years so it's not a new software program, although like I said, your update crashed my system. I can't access Firefox, says unable to access runtime

Your latest update crashed my desktop computer. I've had Mozilla for a few years so it's not a new software program, although like I said, your update crashed my system. I can't access Firefox, says unable to access runtime

All Replies (1)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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Sorry to hear about that, sometimes the updater can leave a mix of different-version files in your Firefox program folder. Here's what you need to do if that's the cause of the problem:

Clean Reinstall

We use this name, but it's not about removing your settings, it's about making sure the program files are clean. As described below, this process does not disturb your existing settings. Do NOT uninstall Firefox, that's not needed.

(1) Download a fresh installer for Firefox 37.0.2 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

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

(3) Rename the program folder

(32-bit Windows folder names) 

C:\Program Files\Mozilla Firefox

to 

C:\Program Files\OldFirefox

(64-bit Windows folder names) 

C:\Program Files (x86)\Mozilla Firefox

to 

C:\Program Files (x86)\OldFirefox

(4) Run the installer you downloaded in #1. It should automatically connect to your existing settings.

Any improvement?

Note: Some plugins may exist only in that OldFirefox folder. If something essential is missing, look in these folders:

  • \OldFirefox\Plugins
  • \OldFirefox\browser\plugins