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A copy of Firefox is already open. Only one copy of Firefox can be open at a time. I GET THIS MESSAGE - BUT FIREFOX APPEARS NOT TO BE OPEN.????????

  • 1 reply
  • 22 have this problem
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  • Last reply by John99

i have already deleted (trashed) all versions of firefox, and then re-downloaded the new Firefox, and when i try to open it, i get the message, "A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

i have already deleted (trashed) all versions of firefox, and then re-downloaded the new Firefox, and when i try to open it, i get the message, "A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

All Replies (1)

Make sure you allow Firefox a few minutes to close down,and always use the menu options to close Firefox (Not just closing a window or killing the process).

Just for now Look for Firefox processes or plugin container that are still running and kill them before trying again.