Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox suddenly won't open. Error mssg c:\Program Files (86)\Mozilla Firefox\firefox.exe

  • 2 replies
  • 1 has this problem
  • 1 view
  • Last reply by Skippy1985

more options

I can't get firefox to open. It worked fine up until 2 days ago. Now, when I try to open it I get an error message with the above-mentioned address. When I right click on the firefox icon and look at properties it tells me the Target address is not correct or has been moved and asks if I want to get rid of the icon. I just want to get Firefox back. Can anyone help?

I can't get firefox to open. It worked fine up until 2 days ago. Now, when I try to open it I get an error message with the above-mentioned address. When I right click on the firefox icon and look at properties it tells me the Target address is not correct or has been moved and asks if I want to get rid of the icon. I just want to get Firefox back. Can anyone help?

Chosen solution

Hi Skippy1985, 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. You do not need to uninstall Firefox first.

It only takes a few minutes.

(A) Download a fresh installer for Firefox 50.1.0 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.) Choose the "Windows" version (32-bit) rather than the 64-bit version for maximum plugin compatibility (and of course for 32-bit Windows systems).

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

(C) Using Windows Explorer/My Computer, rename the program folder as follows -- assuming the folder still exists:

32-bit Firefox on 64-bit Windows: Rename

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\OldFirefox

Other combinations: Rename

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.

Any improvement?

Read this answer in context 👍 0

All Replies (2)

more options

Chosen Solution

Hi Skippy1985, 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. You do not need to uninstall Firefox first.

It only takes a few minutes.

(A) Download a fresh installer for Firefox 50.1.0 from https://www.mozilla.org/firefox/all/ to a convenient location. (Scroll down to your preferred language.) Choose the "Windows" version (32-bit) rather than the 64-bit version for maximum plugin compatibility (and of course for 32-bit Windows systems).

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

(C) Using Windows Explorer/My Computer, rename the program folder as follows -- assuming the folder still exists:

32-bit Firefox on 64-bit Windows: Rename

C:\Program Files (x86)\Mozilla Firefox

to

C:\Program Files (x86)\OldFirefox

Other combinations: Rename

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.

Any improvement?

more options

Couldn't find the file as you suggested so I couldn't rename the file. However, I ran the downloaded installer and everything works just fine now. Thanks for the help!