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!

Hi Onlinel,
some of these things can be difficult to uninstall, and may affect other browsers not just Firefox. I guess they are designed to be difficult to uninstall.

Uninstall the obvious junk or unwanted programs using Firefox addons manager and then also using the Windows Control panel. A tip there is to look at programs by install date to pick up junk bundled on the same install. Next scan for malawre and adware using multiple tools and hopefully remove more. Finally use the search reset addon that will take settings back to normal. One other thing you may need to do is check icons and shortcuts used by Firefox have not been modified. Appending a site address will cause Firefox to open that site.

Generally there is no need to attempt manual cleanups of the Windows registry or use general registry cleaners unless instructed individually by a specialist malware removal forum.

Post back to say what you have done ad how you get on.

See also Remove a toolbar that has taken over your Firefox search or home page

General Malware removal advice

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
• AdwCleaner: (for adware)
• Kaspersky Free security scan

You need to use multiple and up-to-date tools as they will not all pick up the same things.

Microsoft Security Essentials is a good FREE 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. Note the suggestion to use the Search Reset addon after removing the malware.

Hopefully any malware will be easily detected and removed. I would not suggest you try any manual hacks or edits of the Windows registry. (Once rogue files are removed any residual registry entry will not normally do any harm.)

THANK YOU SO MUCH FOR YOUR EASY TO FOLLOW HELP AND ADVICE! I REALLY appreciate it! I deleted unwanted stuff and then ran a malware scan, which fixed it! I hadn't heard of 'malware' before. THANK YOU THANK YOU THANK YOU BOTH SO MUCH x

You are welcome. Glad we were able to help you fix the problem & thanks for posting back.

Often some of these sorts of unwanted software are bundled with other things, or is malware from a none reputable site. It is worth trying to get reviews of software and the download sites before you use them. Then when downloads are offered and in progress look carefully at any additional information about what else is being provided, you may have to opt out of extras.

Hello, You can follow this free removal guide: http://malwaretips.com/blogs/remove-trovi-virus/

Stay safe!