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Firefox will not start

  • 5 replies
  • 1 has this problem
  • Last reply by jchauhan

jchauhan
jchauhan
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When I try to start Frefox I get the following error message

The instruction at "0x7b9777a9" referenced memeory at "0x7b9777a9". The memory could not be "read".

Click OK to terminate the program.

When I try to start Frefox I get the following error message The instruction at "0x7b9777a9" referenced memeory at "0x7b9777a9". The memory could not be "read". Click OK to terminate the program.

All Replies (5)

Morbus
Morbus
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Hopefully this support article is what you need:

https://support.mozilla.com/en-US/kb/Firefox+will+not+start

jchauhan
jchauhan Question owner
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Thanks for the help - this unfortunately did not resolve my problem.

Morbus
Morbus
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Can you please try it in a new (temporary) Firefox profile and see if the issue is still present? See this article to know how to create a new Firefox profile. Please report back the results.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).
See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

If it does work in Safe-mode then disable all your extensions and then try to find which is causing it by enabling one at a time until the problem reappears.
You can use "Disable all add-ons" on the Safe mode start window to disable all extensions.
You have to close and restart Firefox after each change via "File > Exit" (Mac: "Firefox > Quit"; Linux: "File > Quit")

jchauhan
jchauhan Question owner
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Thank you to everyone who provided me with help on this. I tried pretty much everything suggested and in the end decided to reformat C-drive and start all over again.