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.

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

Firefox crashes on opening

  • 3 replies
  • 1 has this problem
  • 4 views
  • Last reply by FredMcD

more options

Firefox 56.0.1 (latest auto update) Every attempt to start (in normal and safe mode) results in Application error "The instruction at 0x3fc69352 referenced memory at 0x00000000. The memory could not be read". Main screen is showing, error window will close, but firefox unresponsive to browsing instructions.

System is 64bit running Windows 7 Home Edition SP 1.

Worked fine until most recent autoupgrade.

Firefox 56.0.1 (latest auto update) Every attempt to start (in normal and safe mode) results in Application error "The instruction at 0x3fc69352 referenced memory at 0x00000000. The memory could not be read". Main screen is showing, error window will close, but firefox unresponsive to browsing instructions. System is 64bit running Windows 7 Home Edition SP 1. Worked fine until most recent autoupgrade.

Chosen solution

Are you using the 64bit Firefox? Many have reported issues. Install the 32bit version from; Download Firefox For All languages And Systems {web link}

Read this answer in context 👍 0

All Replies (3)

more options

Chosen Solution

Are you using the 64bit Firefox? Many have reported issues. Install the 32bit version from; Download Firefox For All languages And Systems {web link}

more options

Downloading 32bit made it work (despite being a 64bit m/c!!!). Thanks

more options

Glad to help. Safe Surfing.