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Trying to open Firefox today I get the message: A copy of Firefox is already open. Only one copy of Firefox can be open at a time. 'm stuck!

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  • Last reply by FredMcD

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I can't access Firefox. Get message: A copy of Firefox is already open. Only one copy of Firefox can be open at a time.

Firefox is not open and I need it!

I can't access Firefox. Get message: A copy of Firefox is already open. Only one copy of Firefox can be open at a time. Firefox is not open and I need it!

Chosen solution

Macs: Make sure you install Firefox properly and that you do not run Firefox from within the DMG (Disk Images) file. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

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iMac OS 11.3.1 Can't identify FF version as can't open it! Can't find FF in library or app support so can't find profile Really stuck.

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Chosen Solution

Macs: Make sure you install Firefox properly and that you do not run Firefox from within the DMG (Disk Images) file. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

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Thank you so much! I didn't quite understand everything but by some magic it worked!! And Firefox is back with me and all seems to be in order.

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Glad to help. Safe Surfing.