The profiles aren't the issue, it's running two copies of Thunderbird. You could run one regular TB and one portable TB. Or have two desktop icons, one for each profile, using the target in icon set to something such as "thunderbird.exe" -profile "c:\profile1" Or the easiest is to set one desktop icon with the -p parameter (for Profile Manager) and at startup, select the desired profile. Anyway, yes, it's doable. But I haven't done this is awhile and would need to recheck the syntax I'm giving you. I'm signing off for the day, and if you haven't heard from anyone else, I'll recheck this later.

OOPS: Correction. You said two copies of thunderbird. That's a different animal. On that, I suggest the safest approach would be one regular installation and one portable. You could use one regular and one beta, but I wouldn't recommend it.

Thanks, will wait for your reply.

Ok, i see the difficulty, will look at other solutions

Okay, it's easy. create a desktop icon for thunderbird. just right-click, browse to the location of thunderbird and click thunderbird.exe and save. that gives you a desktop link to thunderbird. Now, right-click on the icon and click properties. On target line, to right of thunderbird.exe, add a space, the -profile then (in quotes) the location on disk of the profile. My suggestion is to put the profiles in root, so that the resulting target will appear as (assuming profile name is profile1:

 ...thunderbird.exe -profile "c:\profile1"

Create two such icons and rename as desired.