Hi gjlink, When I search for this error, all of the results are suggesting to run a malware scan. Please do this first and then try a clean reinstall: 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: * [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/faq/?qid=208283363 TDSSKiller - AntiRootkit Utility] * [http://www.surfright.nl/en/hitmanpro/ Hitman Pro] * [http://www.eset.com/us/online-scanner/ ESET Online Scanner] [http://windows.microsoft.com/MSE 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. * Certain Firefox problems can be solved by performing a ''Clean reinstall''. This means you remove Firefox program files and then reinstall Firefox. Please follow these steps: '''Note:''' You might want to print these steps or view them in another browser. #Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer. #After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu). #Delete the Firefox installation folder, which is located in one of these locations, by default: #*'''Windows:''' #**C:\Program Files\Mozilla Firefox #**C:\Program Files (x86)\Mozilla Firefox #*'''Mac:''' Delete Firefox from the Applications folder. #*'''Linux:''' If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see [[Installing Firefox on Linux]]. If you downloaded and installed the binary package from the [http://www.mozilla.org/firefox#desktop Firefox download page], simply remove the folder ''firefox'' in your home directory. #Now, go ahead and reinstall Firefox: ##Double-click the downloaded installation file and go through the steps of the installation wizard. ##Once the wizard is finished, choose to directly open Firefox after clicking the Finish button. More information about reinstalling Firefox can be found [[Troubleshoot and diagnose Firefox problems#w_5-reinstall-firefox|here]]. <b>WARNING:</b> Do not run Firefox's uninstaller or use a third party remover as part of this process, because that could permanently delete your Firefox data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. <u>These cannot be easily recovered unless they have been backed up to an external device!</u> Please report back to say if this helped you! Thank you.