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NTVDM CPU has encountered an illegal instruction using Windows XP Firefox 8.0.1 (IE8 does not cause this error)

  • 1 reply
  • 8 have this problem
  • 5 views
  • Last reply by cor-el

bmurray
bmurray

C:\Windows\install~1\{AC76B~1\SC_ACR~1.EXE The NTVDM CPU has encountered an illegal instruction. CS:0dd8 IP:01be OP:ff ff ff 00 00 Choose 'Close' to terminate the application.

I receive the error every time I turn on and off my pc and then start Mozilla Firefox. The problem does not happen if I use IE8.

I have gone to the control panel and removed Firefox 8.0.1 and then downloaded a new version and installed. I still experience the issue.

C:\Windows\install~1\{AC76B~1\SC_ACR~1.EXE The NTVDM CPU has encountered an illegal instruction. CS:0dd8 IP:01be OP:ff ff ff 00 00 Choose 'Close' to terminate the application. I receive the error every time I turn on and off my pc and then start Mozilla Firefox. The problem does not happen if I use IE8. I have gone to the control panel and removed Firefox 8.0.1 and then downloaded a new version and installed. I still experience the issue.

All Replies (1)

cor-el
cor-el
  • Moderator

Make sure that you do not run Firefox in compatibility mode.
You can open the Properties via the right-click context menu of the Firefox desktop shortcut and check that in the "Compatibility" tab.
Make sure that all items are deselected in the "Compatibility" tab of the Properties window.