We're sorry to hear that your Firefox seems to be crashing when you open it. Please perform the following steps to give us a crash report ID that helps us find out more about the cause of the crash.

1. On the keyboard, press [Windows] The image "Windows key" does not exist. + [R]. This should bring up a Run window that contains a text field.
2. In that text field, type %APPDATA% and press Enter. An explorer window should open.
3. From that explorer window, double-click on the Mozilla folder, then double-click on Firefox and then on Crash reports. Double-click on submitted.
4. Now, you should see a list of files that contain reports. Go to View > Arrange Icons by > Modified to get the most recent files at the top of the window.
5. Open the most recent 5 files with a text editor and copy the IDs.
6. Paste each ID with bp- into the reply window on the forums.

Thanks in advance!

You can find more information and troubleshooting steps in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

The location you referenced does not exist. I do however have an events folder.

hm, when there isn't a Mozilla Crash Reporter windows popping up at the time of the crashes, it's going to be very hard to know what's going wrong unfortunately...

crash.main.2 1541525763 c0746232-f1fc-492b-9ee0-1ae206df24a2 ServerURL=https://crash-reports.mozilla.com/submit?id={ec8030f7-c20a-464f-9b0e-13a3a9e97384}&version=60.3.0&buildid=20181017185317 StartupTime=1541525763 SafeMode=0 ProductName=Firefox Vendor=Mozilla InstallTime=1541456681 CPUMicrocodeVersion=0x22 ReleaseChannel=esr Version=60.3.0 AppInitDLLs=%ProgramFiles%\\Sophos\\Sophos Anti-Virus\\\\sophos_detoured.dll;%ProgramFiles%\\Sophos\\Sophos Anti-Virus\\sophos_detoured.dll StartupCrash=1 BuildID=20181017185317 ProductID={ec8030f7-c20a-464f-9b0e-13a3a9e97384} CrashTime=1541525763 UptimeTS=3.127058971 in event folder: Filename:c0746232-f1fc-492b-9ee0-1ae206df24a2 FileContents: SecondsSinceLastCrash=693 SystemMemoryUsePercentage=33 TotalVirtualMemory=4294836224 AvailableVirtualMemory=4048801792 TotalPageFile=17087119360 AvailablePageFile=14110339072 TotalPhysicalMemory=8497184768 AvailablePhysicalMemory=5666119680 ThreadIdNameMapping=

Does the information provided help at all?

thanks, it might be the "Sophos Intercept X"/"Exploit Prevention" feature of your security software that's interfering with the browser this way. can you try to disable that or add firefox to a list of whitelisted programs and see if this is making a difference?

I'm aware that virus protection can sometimes cause issues with software, so yesterday evening I uninstalled all Sophos products and did a full removal and clean install of FF 60.3.0. I got the same results.

ok, then i think we'll still need a successfully submitted crash report id starting with bp-... to know what's going on. if more than one system was affected perhaps you can dig anything up from the %appdata%\Mozilla\Firefox\Crash reports\submitted folder of a different pc?

Error message : The application had a problem and crashed. Unfortunately, the Crash Reporter is unable to submitt a report for this crash. Details: The application did not leave an application data file.

Same error message and results on all four tested systems.

Located a file named Last Crash in the root of that directory that updates date and time with each crash. Contents: 1541426775. No clue what that is.

I found the problem...We use Ivanti (Formerly AppSense) to manage user profiles. When the configuration is removed Firefox launches. Thanks for your help. I'll take it from here.

great, thanks for following up with your findings :))