Hi I am trying to migrate all email and calendars from Mac (Mojave) to Ubuntu I was using the latest version that I could install on Mac - I cannot recall the version number but I have been using Thunderbird on Mac for about 12 years and just updated as releases were available. I have 12 years of Email data and Calendars etc that I am unable to lose and require as I move forward. I copied my Thunderbird folder that was stored within the Library folder on Mac After installing Thunderbird on Linux (Ubuntu) I assumed that I would simply have to do the following:- Edit the install and profile files to reflect my existing profile coming from Mac Delete the default profile created by Thunderbird upon startup/installation copy the profile folder from Mac on to the Linux box Start Thunderbird Upon starting Thunderbird I get the following :- You have launched an older version of Thunderbird ...... Create New Profile | Quit I tried creating a new profile then copying all data to that profile but I get the same message? I have read through the standard migration guides offered on the Thunderbird site but very similar to the process I have carried out wit the same (not working) result. Is anyone able to provide a more detailed guide to complete this process allowing me to preserve all current and historical data? Many thanks