Delete the profiles.ini file to force Firefox to create a new profiles.ini file and a new default profile.

• http://kb.mozillazine.org/profiles.ini_file

Note that Windows hides some file extensions by default.
Among them are .html and .ini and .js and .txt, so you may only see a name without file extension. You can see the real file type if you open the Properties via the right-click context menu

• http://kb.mozillazine.org/Profile_folder_-_Firefox

• http://kb.mozillazine.org/Profile_in_use
• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.

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

• Microsoft Safety Scanner
• MalwareBytes' Anti-Malware
• TDSSKiller - AntiRootkit Utility
• Hitman Pro
• ESET Online Scanner

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.

Did this fix your problems? Please report back to us!

Thank you for your replies! I ran SpyBot, and it didn't detect anything. I deleted the profiles.ini file, which allows me to open Firefox, but then it closes after about a minute of use. I can now open it in safe mode without it crashing, though... What should I do now?

Hello,

Try disabling graphics hardware acceleration. Since this feature was added to Firefox, it has gradually improved, but there still are a few glitches.

You might need to restart Firefox in order for this to take effect, so save all work first (e.g., mail you are composing, online documents you're editing, etc.).

Then perform these steps:

• Click the orange Firefox button at the top left, then select the "Options" button, or, if there is no Firefox button at the top, go to Tools > Options.
• In the Firefox options window click the Advanced tab, then select "General".
• In the settings list, you should find the Use hardware acceleration when available checkbox. Uncheck this checkbox.
• Now, restart Firefox and see if the problems persist.

Additionally, please check for updates for your graphics driver by following the steps mentioned in the following Knowledge base articles:

• Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

• Upgrade your graphics drivers to use hardware acceleration and WebGL

Did this fix your problems? Please report back to us!

Thank you.

After restarting my computer, it seems like deleting the profiles.ini file worked! Firefox, at least so far, has stopped crashing! If it does it again, I'll play with the graphics hardware acceleration. Thank you all so much for your help!!!