You should always pay attention when installing software because often, a software installer includes optional installs, such as this adware. Be very careful what you agree to install.<br> Adware gets on your computer after you have installed a freeware software (video recording/streaming, download-managers or PDF creators) that had bundled into their installation this browser hijacker. You can use the below steps to revert back to adware-less Firefox. ---- 1) Remove any programs that you don't recognize or remember installing from your Control Panel (Start > Control Panel > Uninstall a Program) ---- 2) Download ADW Cleaner to wipe out any remnants of the adware. *http://www.bleepingcomputer.com/download/adwcleaner/ ---- 3) Do a malware check with some malware scanning programs on the Windows computer.<br> Please scan with all programs because each program detects different malware.<br> All these programs have free versions. Make sure that you update each program to get the latest version of their databases before doing a scan. *Malwarebytes' Anti-Malware:<br>http://www.malwarebytes.org/mbam.php *SuperAntispyware:<br>http://www.superantispyware.com/ *Microsoft Safety Scanner:<br>http://www.microsoft.com/security/scanner/en-us/default.aspx *Windows Defender: Home Page:<br>http://www.microsoft.com/windows/products/winfamily/defender/default.mspx *Spybot Search & Destroy:<br>http://www.safer-networking.org/en/index.html *Kasperky Free Security Scan:<br>http://www.kaspersky.com/security-scan You can also do a check for a rootkit infection with TDSSKiller. *Anti-rootkit utility TDSSKiller:<br>http://support.kaspersky.com/5350?el=88446 See also: *"Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked ---- 4) it looks like user.js is currently active in Firefox. The user.js file is only present if you or other software has created this file and normally it wouldn't be there. You can delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release. You can get to the profile folder below: *Help > Troubleshooting Information > Profile Directory > Show Folder or *Go to '''about:support''' and click Show Folder next to Profile Directory.