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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

Posted

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

Additional System Details

Application

  • User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.104 AOL/9.8 AOLBuild/4346.1014.US Safari/537.36

More Information

Question owner

It also said XULRUNNER at the top...

It also said XULRUNNER at the top...
jscher2000
  • Top 10 Contributor
8315 solutions 68040 answers

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
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

Question owner

Thanks so much, its working great now and connected to my old settings! Thanks again and Happy New Year!

Thanks so much, its working great now and connected to my old settings! Thanks again and Happy New Year!