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firefox won't launch in Windows 7 after update

  • 23 replies
  • 2 have this problem
  • Last reply by FredMcD

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Since the last update to Firefox 65, it won't launch on my Windows 7 64 bit. It shows in the running process. I've gone through all the forums and helps. I've checked compatibility, cleared out my allowable programs and re-entered, checked my Windows defender, plus everything else I could find. It would not open in safe mode although I tried something once (no idea what) and it did open briefly to save my bookmarks but then I couldn't get out or back in. I'm at a loss what to do at this point and I really like Firefox. I'm not savvy with computers but I know some and can follow directions. Firefox worked fine until the update and nothing has changed on my computer since that point except downloading Chrome to have a browser.

All Replies (3)

more options You may have corrupt xulstore.json or Localstore.rdf files.

Close Firefox. Open your file browser to this hidden location:

  • Mac: *~/Library/Application Support/Firefox/Profiles
  • Linux: *~/.mozilla/firefox/Profiles
  • Windows: %AppData%\Mozilla\Firefox\Profiles
  • *C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles
  • Windows XP: C:\Documents and Settings\<user>\Application Data

Search for the above files. Then rename or delete them. Restart Firefox.

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I don't have either of these files in Firefox profile folder. I do have them for Thunderbird.

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Do you have the Firefox icon on your quick launch? Right click on it, and select Open New Window. Sometimes this works. If it opens, close it by Menu > File > Exit.

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