I often run multiple versions of Firefox at the sane time but do not automate that and am not aware what ''Autoit'' is also I prefer using Linux to Windows. Unfortunatly the crash reports do not help in this instance they did not collect any useful information. I wonder if the problem is the use of Autoit if that is the only time Firefox crashes and it is not version or profile specific.

Try to disable hardware acceleration in Firefox. *Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available" *https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes *https://hacks.mozilla.org/2010/09/hardware-acceleration/ Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps. ---- Do a malware check with some malware scanning programs on the Windows computer.<br /> You need to scan with all programs because each program detects different malware.<br /> Make sure that you update each program to get the latest version of their databases before doing a scan. *http://www.malwarebytes.org/mbam.php - Malwarebytes' Anti-Malware *http://www.superantispyware.com/ - SuperAntispyware *http://www.microsoft.com/security/scanner/en-us/default.aspx - Microsoft Safety Scanner *http://www.microsoft.com/windows/products/winfamily/defender/default.mspx - Windows Defender: Home Page *http://www.safer-networking.org/en/index.html - Spybot Search & Destroy You can also do a check for a rootkit infection with TDSSKiller. *http://support.kaspersky.com/viruses/solutions?qid=208280684 See also: *"Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked