Firefox keeps opening as multiple windows and becomes unresponsive. What's wrong?
On clicking Start and selecting Firefox, Firefox proceeds to open as two separate windows, each with multiple tabs and quickly becomes unresponsive (suspect overloading system). Windows then pops up an error message that the program is unresponsive and invites forced shutdown. The shutdown and reporting process can take several minutes. Repeated tries, even after re-booting my system results in similar results
Additional System Details
Every time Firefox opened
This started when...
- User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; .NET CLR 1.1.4322; .NET4.0C; .NET4.0E)
You can check the home page setting.
It is possible that there is a problem with the files sessionstore.js and sessionstore.bak in the Firefox Profile Folder.
Delete the sessionstore.js  file and possible sessionstore-##.js  files with a number and sessionstore.bak in the Firefox Profile Folder.
- Help > Troubleshooting Information > Profile Directory: Open Containing Folder
Deleting sessionstore.js will cause App Tabs and Tab Groups and open and closed (undo) tabs to get lost, so you will have to create them again (make a note or bookmark them).
thanks for the info, cor-el, but it didn't work for me. First, I cannot open Firefox without its immediately freezing up and becoming unresponsive; second, I followed the directions to open the Profile folder only to be confronted with a folder called: zOcxOoe2.default. this contains further subfolders but none appear to contain any files called sessionstore.js or sessionstore.bak as you describe.
I'm now even more confused. What now please?
Windows may hide the file extension, so you may only see files with a sessionstore name. You can check the file type via the Properties in the right-click context menu to be sure.
I'm sorry to seem obtuse, cor-el, but nothing that you have said makes any sense to me. I'm unable to make any sense of the myriad folders contained in the 'Profiles' folder, let alone discover what files are in them and when I do, none bear any relationship to ones you describe
Last time I had this kind of problem it was with a beta version of Firefox and the only solution that seemed to work was to un-install Firefox altogether and start again with an earlier, stable version. I then had the agony of trying to restore all my bookmarks etc.
If it hadn't been for the existence of my Macbook Pro running Safari, I'd really be having problems right now.