Hi, this sounds like a malware issue, so you can try these free programs to scan for malware, which work with your existing antivirus software: * [http://www.microsoft.com/security/scanner/default.aspx Microsoft Safety Scanner] * [http://www.malwarebytes.org/products/malwarebytes_free/ MalwareBytes' Anti-Malware] * [http://support.kaspersky.com/viruses/disinfection/5350 Anti-Rootkit Utility - TDSSKiller] * [http://general-changelog-team.fr/en/downloads/viewdownload/20-outils-de-xplode/2-adwcleaner AdwCleaner] (for more info, see this [http://www.bleepingcomputer.com/download/adwcleaner/ alternate AdwCleaner download page]) * [http://www.surfright.nl/en/hitmanpro/ Hitman Pro] * [http://www.eset.com/us/online-scanner/ ESET Online Scanner] '''Note that not all removal programs will detect all malware, so you may need to run several or all of them.''' [https://support.microsoft.com/help/14210/security-essentials-download Microsoft Security Essentials] is a good permanent antivirus for Windows 7/Vista if you don't already have one. Windows 8/10 have antivirus protection [https://www.microsoft.com/windows/windows-defender built-in]. Further information can be found in the [[Troubleshoot Firefox issues caused by malware]] article. You can also check your Firefox Desktop shortcut for corruption: Right click on it > Properties, and in Target, make sure there is nothing other than Firefox. If there is, delete that part of it. Or if it's easier, you can just delete it and recreate a new shortcut. More: [[Wrong home page opens when I start Firefox - How to fix]]. ''If your question is resolved by this or another answer, please take a minute to let us know. Thank you!''