Hi, Kmkriel, I did some research on the add on and all that came up are the crashes for that add on. Please disable the add on and see if the error message continues. After reading about the add on, it seems that ClamAV/ClamWin needs to be installed in order for the scan to take place before the download. If this continues when the add on is disabled please do a virus scan. 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. Did this fix your problems? Please report back to us!

Note that you also seem to have Norton software and Firefox extensions installed.<br /> Having two AV programs installed and activated at the same time is not recommended as this can cause issues.<br /> In such cases it is better to have one enabled and set the other to scan manually on demand.