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My firefox crashed and I re-installed it. Now it says one copy of firefox already running and the software does not open

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My firefox crashed and I re-installed it. Now when after re-installing I tried to open the application, it gives me a message that a copy of firefox is already running and you cannot open another copy of the software.

I checked and removed all firefox documents and re-installed but the same problem occurs.

My firefox crashed and I re-installed it. Now when after re-installing I tried to open the application, it gives me a message that a copy of firefox is already running and you cannot open another copy of the software. I checked and removed all firefox documents and re-installed but the same problem occurs.

All Replies (10)

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What's your computer system and Firefox version?

Reboot the computer. Is the problem still there?

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Mac OS X Yosemite 10.10.5

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rebooted. no help. have attached a screenshot of the error

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From the time you booted up, describe what you did that lead up to the error message.

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I tried this, but could not find firefox running in the activity monitor.

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I re-installed firefox and tried to open it. Got the same error message

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Did you do a clean install? (Removing all program folders)

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Yup I removed everything