Sorry you are having problems. Something has gone badly wrong.No idea why, but that is not intended to happen. (IIRC There may have been other similar reports recently but I do not have time to look now) First of all lets say it is unwise to stop Firefox updating because there are security risks with running unsupported insecure old versions. Secondly the automated upgrades are intended to retain bookmarks and other things. The import option should be used with caution it will overwrite the existing bookmarks. It is good practice to * routinely and regularly make your own manual backups<br />[[Restore bookmarks from backup or move them to another computer]] ** or use sync if you have a 2nd device, so that device is effectively a backup. <br /> [[Firefox Sync - Take your bookmarks, tabs and personal information with you]] ---------- Now to the problem of missing bookmarks. As I do not know exactly what occurred i am not certain they can be recovered, but lets make sure we have whatever is available, and put it somewhere safe. * see also [[Recover lost or missing Bookmarks]] These are stored in # ''places.sqlite'' a database within your Firefox settings folder ( [[Profiles - Where Firefox stores your bookmarks, passwords and other user data|profile]] ) # some separate backup files again within the profile, and in a sub folder with a name something like ''bookmarkbackups'' with files that will include a date and end with (possibly hidden) file extension''.json '' You need to #Find the existing files, and back them up by making copies #* an easy method of finding the profile is to use <br/> '''Firefox Button -> Help -> Troubleshooting''' <br /> or key in ''about:support'' <br /> then use [open folder] or whatever the wording #*place the copies somewehre safe. Outside of Fifrefox program or profile paths. (Your Windows Desktop is suitable) # it is also worth looking to see if there are previous versions of the files available #*You MUST backup the current versions first #*Recent versions of Windows may allow you to recover previous versions of some files, and that could; by default; include the profile content. <br /> http://windows.microsoft.com/en-US/windows7/Previous-versions-of-files-frequently-asked-questions Please now <br /> Read the linked articles. <br/>Find the files mentioned and and back them up. <br /> See if previous copies exist. Post back with how you get on, and I or someone else will help with the next steps.

Did you try to reboot the computer? *http://kb.mozillazine.org/Standard_diagnostic_-_Firefox