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

Getting an error message "Windows cannot find 'C:\Windows\Program Files\Mozilla Firefox\firefox.exe'." when launching firefox without being unable to use it

  • 5 replies
  • 5 have this problem
  • 22 views
  • Last reply by ideato

more options

Hello!

It happened since I had a virus a month ago which prevented the computer to start. It came back from the repair shop and it starts again now. But, after a few hours of use of Firefox, this message pop up randomly: "Windows cannot find 'C:\Windows\Program Files\Mozilla Firefox\firefox.exe'. Make sure you typed the name correctly, and then try again." Example: http://www.risingroad.com/foxhound/faq/images/Windows%20cannot%20find%20firefox.jpg

and Firefox still works after this message pops up. I've already uninstalled and installed Firefox again completely, and the message still shows up; what does it means and is it dangerous for the computer?

I'm under Windows 8

Hello! It happened since I had a virus a month ago which prevented the computer to start. It came back from the repair shop and it starts again now. But, after a few hours of use of Firefox, this message pop up randomly: "Windows cannot find 'C:\Windows\Program Files\Mozilla Firefox\firefox.exe'. Make sure you typed the name correctly, and then try again." Example: http://www.risingroad.com/foxhound/faq/images/Windows%20cannot%20find%20firefox.jpg and Firefox still works after this message pops up. I've already uninstalled and installed Firefox again completely, and the message still shows up; what does it means and is it dangerous for the computer? I'm under Windows 8

Chosen solution

I've had the feeling pop up ads may cause the problem and talked about this to my father's computer engineer. He installed Malewarebytes and there was indeed still a maleware left by repair men. The difference was, Chrome used to show the full ad page while Firefox may have by now a security to block that kind of page and the result was the error message. (I didn't know that, since it happened to me on my to previous computers and even Firefox used to show me the ad then) Thanks for warning me.

Read this answer in context 👍 1

All Replies (5)

more options

Hello Sarahime, try these free programs to scan for malware, which work with your existing antivirus software:

Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

thank you

more options

I have Avast, it didn't detected any viruses.

more options

Please scan with all the above programs because each one detects different malware.

thanks again

more options

Chosen Solution

I've had the feeling pop up ads may cause the problem and talked about this to my father's computer engineer. He installed Malewarebytes and there was indeed still a maleware left by repair men. The difference was, Chrome used to show the full ad page while Firefox may have by now a security to block that kind of page and the result was the error message. (I didn't know that, since it happened to me on my to previous computers and even Firefox used to show me the ad then) Thanks for warning me.

more options

you are welcome