If you have submitted crash reports then please post the IDs of one or more recent crash reports that start with "bp-". *bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx You can find the report ID of recent crash reports on the "Help -> Troubleshooting Information" (about:support) page. *click the "All Crash Reports" button on this page to open the <b>about:crashes</b> page and see all crash reports. Alternatively you can open about:crashes via the location/address bar. See also: *https://support.mozilla.org/en-US/kb/Mozilla+Crash+Reporter If you can't start Firefox, see: How to get the crash ID if Firefox crashes on startup *https://developer.mozilla.org/en-US/How_to_get_a_stacktrace_for_a_bug_report

bp-d1336930-e53b-43e9-ab2e-2a37e0190626 bp-c58cac1d-51b4-461c-9512-678a30190626 bp-8dfcddc3-0184-4efe-9ce1-ce58f0190626

The crashing thread in all three reports have a call to WindowsDllBlocklist.cpp:712 at to bottom of the thread. So it is possible that you have files that are on the DLL block list and that aren't playing nicely when Firefox tries to (re)move them. Boot the computer in Windows Safe mode with network support to see if that has effect in case other software is causing problems. *http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/ *http://www.7tutorials.com/4-ways-boot-safe-mode-windows-10 ---- Do a malware check with several malware scanning programs on the Windows computer. *https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware Please scan with all programs because each program detects different malware. All these programs have free versions. Make sure you update each program to get the latest version of their databases before doing a scan. *Malwarebytes' Anti-Malware:<br>https://www.malwarebytes.com/ *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>https://www.microsoft.com/security/scanner/en-us/default.aspx *Windows Defender:<br>https://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>https://www.kaspersky.com/security-scan You can also do a check for a rootkit infection with TDSSKiller. *Anti-rootkit utility TDSSKiller:<br>https://support.kaspersky.com/viruses/disinfection/5350 <br>https://support.kaspersky.com/viruses/utility