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Whenever I launch firefox (44.0.2) for Mac I get an error that says "another copy of firefox is already open". How do i fix this? It's driving me crazy!

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

wayne36
wayne36
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Mac OS 10.6.8 Error only happens at start-up and can be dismissed. Once dismissed, the browser works perfectly. I've seen fixes for this problem for Windows but not Mac. Adobe Flash totally disabled.

Mac OS 10.6.8 Error only happens at start-up and can be dismissed. Once dismissed, the browser works perfectly. I've seen fixes for this problem for Windows but not Mac. Adobe Flash totally disabled.

Chosen solution

Thanks for your suggestion, but I think that I located the source of the problem: the RoboForm toolbar. After I posted my original question, I discovered that if I evoked RoboForm to fill-in a password, I was also getting the "another copy of Firefox is already open" error, and RoboForm would not work. So, that seemed too coincidental to me. I deleted the RoboForm add-on and reinstalled it. The error disappeared and RoboForm is working again!

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All Replies (3)

FredMcD
FredMcD
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Check and see if Firefox is already running first. Then start the browser. Is the problem still there?

wayne36
wayne36 Question owner
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Chosen Solution

Thanks for your suggestion, but I think that I located the source of the problem: the RoboForm toolbar. After I posted my original question, I discovered that if I evoked RoboForm to fill-in a password, I was also getting the "another copy of Firefox is already open" error, and RoboForm would not work. So, that seemed too coincidental to me. I deleted the RoboForm add-on and reinstalled it. The error disappeared and RoboForm is working again!

FredMcD
FredMcD
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That was very good work. Well Done. Please flag your last post as Solved Problem so others will know.