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I have tried uninstalling and reinstalling Firefox several times. Every time I try to open Firefox I get an error message saying "Close Firefox"," A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

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  • 12 have this problem
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  • Last reply by dougdwr

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I uninstall Firefox, then reinstall Firefox, try to open Firefox, and get an error message in a popup box saying,

"Close Firefox"

"A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

I uninstall Firefox, then reinstall Firefox, try to open Firefox, and get an error message in a popup box saying, "Close Firefox" "A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

Chosen solution

Create a new profile as a test to check if your current profile is causing the problems.

See "Basic Troubleshooting: Make a new profile":

If that new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.

See:

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Chosen Solution

Create a new profile as a test to check if your current profile is causing the problems.

See "Basic Troubleshooting: Make a new profile":

If that new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.

See:

more options

That solved the problem. Thank you very much!!!!