I copied my FF (v43.0.3) profile from a Win XP computer to a (new) Win 10 Home machine. I dropped it in User [user name] appdata Mozilla Firefox. I then installed Firefox. Firefox ignored the profile. I then re-dropped the XP profile over what ever the FF install had done. FireFox accepts the migrating profile "name," but does not recognize anything in that profile (passwords, bookmarks, customized tool bars, etc). In the past, performing this type migration on XP and Vista machines worked perfectly. The profile.ini file contains my migrated profile name. By the way, doing the similar migration to Windows 10 with Thunderbird resulted in a perfect install with all my e-mail accounts, passwords and settings. What are the secrets miograting Firefox to Windows 10?