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Firefox thinks it's already open and won't let me open it.

smarzen
smarzen
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Firefox quit uncleanly. When I try to open it now, I get the error message:

Close Firefox

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

Firefox quit uncleanly. When I try to open it now, I get the error message: Close Firefox A copy of Firefox is already open. Only one copy of Firefox can be open at a time.

All Replies (1)

Wesley Branton
Wesley Branton
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You can use the task manager to end any open Firefox processes. There are likely some open still, even if the Firefox window is not visible.

If you aren't able to do this, simply rebooting your computer should fix the issue because that will close any Firefox processes.