Hi, I use Thunderbird Portable on Flash Drives. I have Thunderbird Portable v 78,12,0 (32-bit) that I use with Windows 10 laptops when I travel. I also have Thunderbird Portable v 52.6.0 (32-bit) that I keep for emergencies that runs on an old Acer Travelmate 2480 with XP. Thunderbird Portable v 78,12,0 (32-bit) will not run on the Acer with XP. I have added several new Mail Accounts to the Thunderbird Portable v 78,12,0 (32-bit). I need to update the mail accounts on the Thunderbird Portable v 52.6.0 (32-bit). My Desktop is broken. I also need to update the mail accounts on my Windows 10 laptop that I am using that has an old version of Thunderbird installed. I am able to copy the “Mail” folder to update the messages with no problem. Copying the Mail Folder does not update the Mail Accounts nor the Address Book. (Contacts) I am thinking that if I copy the entire profile folder, I might be able to get what I want. However, I notice that the “abook” extension is not the same and I wonder what else is not the same and if it will break the v 52.6.0. (abook, histort and impab) Is there an easy way to do what I want?