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I CANNOT OPEN FIREFOX

Tom_798
Tom_798
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It happened suddenly. I can open my I.E. 9 Browser. I get a message that states "couldn't load XPCOM" with a red X in corner of message box when I try to open Firefox. The only change I believe I made was to do a system restore this morning & only restored back about 4- hours. Do you think I'll have to remove Firefox from my programs & features and then reinstall Firefox? Do you have any other suggestions? 

 I am running Windows Vista 32- bit system on a personal computer.

Thank you

It happened suddenly. I can open my I.E. 9 Browser. I get a message that states "couldn't load XPCOM" with a red X in corner of message box when I try to open Firefox. The only change I believe I made was to do a system restore this morning & only restored back about 4- hours. Do you think I'll have to remove Firefox from my programs & features and then reinstall Firefox? Do you have any other suggestions? I am running Windows Vista 32- bit system on a personal computer. Thank you

Chosen solution

System restore often causes strange problems... Here's what I suggest at this point:

(A) Download a fresh installer for Firefox 43.0.2 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

(B) Rename both of those program folders by changing "Mozilla" to "Old": 

C:\Program Files\Mozilla Firefox

to 

C:\Program Files\Old Firefox

and 

C:\Program Files\Mozilla Firefox(0)

to 

C:\Program Files\Old Firefox(0)

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

Will Firefox start?

Read this answer in context 👍 4

All Replies (2)

Tom_798
Tom_798 Question owner
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I just found this in my Program Files. I shows Firefox Programs in 2- places. Please see attached image.

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
more options

Chosen Solution

System restore often causes strange problems... Here's what I suggest at this point:

(A) Download a fresh installer for Firefox 43.0.2 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.)

(B) Rename both of those program folders by changing "Mozilla" to "Old": 

C:\Program Files\Mozilla Firefox

to 

C:\Program Files\Old Firefox

and 

C:\Program Files\Mozilla Firefox(0)

to 

C:\Program Files\Old Firefox(0)

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

Will Firefox start?