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Why do 3 instances of Firefox open at the same time?

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  • 1 has this problem
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  • Last reply by cor-el

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Every time I start up Firefox, 3 different instances of Firefox will open at the same time. Do I need to uninstall it and start over? I don't know why this is happening. When I open IE8 only one page opens; but when I open Firefox 3 tabs open at the same time.

Every time I start up Firefox, 3 different instances of Firefox will open at the same time. Do I need to uninstall it and start over? I don't know why this is happening. When I open IE8 only one page opens; but when I open Firefox 3 tabs open at the same time.

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It is possible that there is a problem with the files sessionstore.js and sessionstore.bak in the Firefox Profile Folder.

Delete the files sessionstore.js and sessionstore.bak in the Firefox Profile Folder.

If you see files sessionstore-##.js with a number in the left part of the name like sessionstore-1.js then delete those as well.
Deleting sessionstore.js will cause App Tabs and Tab Groups to get lost, so you will have to create them again (make a note).

See: