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Firefox window does not open, but it is on the task manager list

  • 9 replies
  • 2 have this problem
  • Last reply by philipp

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As the question says, Firefox does appear on the task manager as open but the window is not actually there. I tried reinstalling it, but it did not help. I also tried running as administrator and in the safe mode - still nothig. I know it did work earlier, then it began to open very slowly and now the window doesn't appear at all. I don't use this computer, my mom does, so I don't know any more details. The system is windows 10 upgraded from windows 8. Hope someone could help me with this.

All Replies (9)

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You may have corrupt xulstore.json or Localstore.rdf file.

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

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

Locate the above files. Then rename or delete them. Restart Firefox.

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Thank you for the answer. I searched the whole location but these files are not there at all.

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If those files were missing, Firefox would recreate them. Did you look in the sub-directories?

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Here's a screenshot of all firefox files I found, the folders visible here are empty.

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I tried using these instruction but the profile manager does not open.

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Not responding? Error message?

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Hi   !
This worked for somebody else the other day:

1 – Head to the Control Panel and click on   'Power Options' 2 – Click the link of the left-hand side   ‘Choose what the power buttons do’ 3 – Click the   ‘Change settings currently unavailable’ link 4 – Tick the   ‘Turn on fast start-up’ box under  'Shut-down' settings

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hi, mozilla just released an update to firefox 49.0.2 that should fix a problem that sound pretty similar to what you've described. you can download this new version from to see if it works for you too.