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

ابحث في الدعم

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

This thread was archived. Please ask a new question if you need help.

nsAppShell:EventWindow: firefox.exe Application error on exiting

  • 1 (رد واحد)
  • 23 have this problem
  • 39 views
  • آخر ردّ كتبه 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