I have two Windows 7 computers running Thunderbird, both are using POP for mail retrieval. I want to take the account from computer A and move it into an existing profile on computer B as a second account. Has anyone done this before? I was reading a vague and hard to follow thread about another person copying files and it not working, hence the question. Here is my plan for migration so far: 1. Open Thunderbird on Computer A. Change the settings to start offline. Write down all of the server settings/configs. 2. Close Thunderbird, copy the %APPDATA% Thunderbird profile to an external device. 3. On Computer B, change the Thunderbird settings for MailDir for new accounts (because these mail profiles are older). Create a new account in Thunderbird under the current profile, using the settings from step 1 except maybe crippling it so it doesn't actually fetch any mail. 4. Close Thunderbird. Copy the backed up mail files from inside the profile, into the folder for the newly created account. 5. Start Thunderbird, uncripple the account so that it begins fetching mail. I'm not certain this will work, I'm confident but not certain. Also this only gets the user's mail transferred, which is a good start but it isn't a complete migration. Additional preferences, saved contacts and such would be missing, is there a way to properly import those as well ? My fallback is to do a full profile migration and place two shortcut's on the desktop, each with the command line parameters for starting with the different profiles. My understanding of Firefox and Thunderbird is that they are single process applications, is it possible for multiple profiles to be launched simultaneously?