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I try to start Firefox and an error message comes up...Platform version 43.0.3 is not compatible with min ver<43.0.2 or max ver>43.0.2 and Firefox will not star

  • 3 replies
  • 8 have this problem
  • 6 views
  • Last reply by mysticjen

mysticjen
mysticjen
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This just started after the new patch.....it was working fine last night and when I went to use it today all I got was the error message.

This just started after the new patch.....it was working fine last night and when I went to use it today all I got was the error message.

Chosen solution

The program folder might have ended up with a mix of different version files. To address that, I suggest:

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. Do NOT uninstall Firefox, that's not needed.

(A) Download a fresh installer for Firefox 43.0.3 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

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

(C) Rename the program folder as follows:

(64-bit Windows folder names) 

C:\Program Files (x86)\Mozilla Firefox

to 

C:\Program Files (x86)\OldFirefox

(32-bit Windows folder names) 

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.

Does a cleanly reinstalled Firefox start up normally??

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

  • \OldFirefox\Plugins
  • \OldFirefox\browser\plugins
Read this answer in context 👍 2

All Replies (3)

mysticjen
mysticjen Question owner
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It also said XULRUNNER at the top...

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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Chosen Solution

The program folder might have ended up with a mix of different version files. To address that, I suggest:

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. Do NOT uninstall Firefox, that's not needed.

(A) Download a fresh installer for Firefox 43.0.3 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

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

(C) Rename the program folder as follows:

(64-bit Windows folder names) 

C:\Program Files (x86)\Mozilla Firefox

to 

C:\Program Files (x86)\OldFirefox

(32-bit Windows folder names) 

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.

Does a cleanly reinstalled Firefox start up normally??

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

  • \OldFirefox\Plugins
  • \OldFirefox\browser\plugins
mysticjen
mysticjen Question owner
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Thanks so much, its working great now and connected to my old settings! Thanks again and Happy New Year!