I have a MacPro which runs three different OSes. I want to boot to any of them and be completely current with my email, so the goal is to locate the Thunderbird Profile to a neutral, non-boot drive that is always available. I have an internal drive in one of my drive bays that is perfect for this. I tried to follow the directions for changing the "profiles.ini" file on my current boot volume, but even with that done, it still makes a new folder. I just want Thunderbird to quit referencing the old location and start referencing the new one. I thought I had updated the "profiles.ini" properly, and, having deleted the actual profile folder within the Profiles folder inside it, it still wanted to create a new one with all the default stuff empty. So it obviously was not looking to the Profile folder I had copied earlier to the neutral drive, even though I put the path in the .ini file and changed the path under [Profile0] and set IsRelative to 0. Should I also have changed the path to the [Install712DAF5A23ABECDC] portion of this .ini file to the new one and unlocked it? Is there a way to ALSO have the "profiles.ini" file and all the apparatus around it on the neutral volume so that EACH version of Thunderbird, no matter which OS is currently booted, accesses this info from there? I wish this kind of instruction was explained better.