This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Hierdie gesprek is in die argief. Vra asseblief 'n nuwe vraag as jy hulp nodig het.

nsAppShell:EventWindow: firefox.exe Application error on exiting

  • 1 antwoord
  • 23 hierdie probleem
  • 39 views
  • Laaste antwoord deur iamjayakumars

Muni123
Muni123
more options

Lately Firefox started acting weirdly, like when I would try to launch the app, it would take very long to start up. So I updated Firefox to the latest version yesterday. After the update, it seemed to launch a little more faster (but still slower then it used to before it started acting oddly). Today, it would not launch at all.

I managed to launch it using 'Run as administrator' and then did a reset. This helped to sort out the launching issue, but now when I close/exit Firefox, I get the error "nsAppShell:EventWindow: firefox.exe Application error. The instruction at 0x77d7e144 referenced memory at 0xffffffff. The memory could not be read. Click on OK to terminate the program".

How do I get this error message to stop showing up? And what is causing this error?

Lately Firefox started acting weirdly, like when I would try to launch the app, it would take very long to start up. So I updated Firefox to the latest version yesterday. After the update, it seemed to launch a little more faster (but still slower then it used to before it started acting oddly). Today, it would not launch at all. I managed to launch it using 'Run as administrator' and then did a reset. This helped to sort out the launching issue, but now when I close/exit Firefox, I get the error "nsAppShell:EventWindow: firefox.exe Application error. The instruction at 0x77d7e144 referenced memory at 0xffffffff. The memory could not be read. Click on OK to terminate the program". How do I get this error message to stop showing up? And what is causing this error?

All Replies (1)

iamjayakumars
iamjayakumars
more options

Create a new profile as a test to check if your current profile is causing the problems.
See Creating a profile:

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over the problem
Profile Backup and Restore