How did you check for malware? It certainly sounds malware-ish. Here's my suggested procedure for tracking down and cleaning up bad add-ons and other hijackers. I know it seems long, but it's not that bad. (1) Open the Windows '''Control Panel''', Uninstall a Program. After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help surface undisclosed bundle items that snuck in with some software you agreed to install. ''Be suspicious of everything you do not recognize/remember, as malware often uses important or innocent sounding names to discourage you from removing it.'' Take out as much trash as possible here. (2) Open Firefox's '''Add-ons page''' using either: * Ctrl+Shift+a * "3-bar" menu button (or Tools menu) > Add-ons * in the Windows "Run" dialog, type or paste <br><code>firefox.exe "about:addons"</code> In the left column, click '''Plugins'''. Set nonessential and unrecognized plugins to "Never Activate". In the left column, click '''Extensions'''. Then, if in doubt, disable (or Remove, if possible) unrecognized and unwanted extensions. ''Bear in mind that all extensions are optional, none come with Firefox.'' Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step. Any improvement? (3) Check for an optional settings file named '''user.js''' in your profile folder (personal settings folder). Firefox uses the settings in that file at startup to override your saved preferences from the previous session. Unless you created that file yourself, it may contains settings from an add-on or external software. You can check and remove the file using the steps in this article: [[How to fix preferences that won't save]]. If you find a file named user but not user.js, Windows may be hiding file extensions from you. To work with files as accurately as possible, I suggest showing all file extensions. This Microsoft support article has the steps: [http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions]. (4) You can search for remaining issues with the '''scanning/cleaning tools''' listed in our support article: [[Troubleshoot Firefox issues caused by malware]]. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case. Success?