If you have submitted crash reports then please post the IDs of one or more recent crash reports that have a "bp-" prefix: *bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx You can find the Report ID of recent crash reports on the "Help > Troubleshooting Information" page (about:support). *Click the "All Crash Reports" button on this page to open the <b>about:crashes</b> page and see all crash reports. If necessary then you can open <b>about:</b> pages via the location/address bar. See: *http://kb.mozillazine.org/Mozilla_Crash_Reporter *https://support.mozilla.org/kb/Mozilla+Crash+Reporter *https://support.mozilla.org/kb/Firefox+crashes ---- Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test. *http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/ Do a malware check with several malware scanning programs on the Windows computer. Please scan with all programs because each program detects different malware. 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 *AdwCleaner:<br>http://www.bleepingcomputer.com/download/adwcleaner/<br>http://www.softpedia.com/get/Antivirus/Removal-Tools/AdwCleaner.shtml *SuperAntispyware:<br>http://www.superantispyware.com/ *Microsoft Safety Scanner:<br>http://www.microsoft.com/security/scanner/en-us/default.aspx *Windows Defender:<br>http://windows.microsoft.com/en-us/windows/using-defender *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

thanks - super useful, now everything works again :-)