Hi cgb0006, backbuttonsucks has posted an answer to your question on support.mozilla.org: How to I rollback after update erased bookmarks and new version cannot access web? backbuttonsucks wrote: Your firefox profile is (most likely) located at the following location: C:\Users\USERNAME\AppData\Roaming\Mozilla\Firefox\Profiles\ it sounds like you have multiple profiles as you say old bookmarks are appearing. Otherwise, you would have to restore this directory from backup. If you have previous versions turned on in windows OS, then you could right click on the folder and go to "previous versions" tab for the automatic backup. Its possible the other profile is there somewhere in that directory. If you have multiple user profiles, take a look a the boomarks.html file to find the correct one. The commands in this article should list all your profiles: https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles?redirectlocale=en-US&redirectslug=Managing+profiles THIS UNFORTUNATELY DOES NOT SOLVE THE APPARENT NETWORKING PROBLEM (NOR WAS I ABLE TO FIND THE OLD BOOKMARKS), AND HAVING CHECKED MY NETWORK PARAMETERS, I SUSPECT THAT THE NEW VERSION IS NOT COMPATIBLE WITH MY OPERATING SYSTEM. I WISH TO BE WALKED THROUGH A ROLLBACK TO MY PREVIOUS VERSION, PREFERABLY WITHOUT HAVING TO PERFORM A SYSTEM RESTORE.