I do exactly what you are trying to do, share my Thunderbird files
between 3 PC's here at home.
It has been a couple of years since I set it up but I'll try to relate
how I did it.
First I copied my Thunderbird files from my original working
Thunderbird setup to my server which is
\\Snow\GlowingBlue\Thunderbird\Profiles\a5fkuk8j.default
My original files were found in the hidden folder of
C:\Users\GlowingBlue\AppData\Roaming\Thunderbird
Don't change anything on the original PC other than editing the
profiles.ini. Make a backup copy of the profiles.ini before you start, I
called mine profiles.old.
Then I modified the Profiles.ini on the original PC to read as:
[InstallD78BF5DD33499EC2]
Default=\\Snow\GlowingBlue\Thunderbird\Profiles\a5ufku8j.default
[Profile0]
Name=default
IsRelative=0
Path=\\Snow\GlowingBlue\Thunderbird\Profiles\a5ufku8j.default
Default=1
[General]
StartWithLastProfile=1
Version=2
The above "[InstallD78BF5DD33499EC2]" was already just as it is and will
most likely be different for your main PC's install of Thunderbird. As
for the a5ufku8j references they were what was already there in the
Profile.ini. The rest is just the path where the copied Thunderbird
profile was placed on the server. I think it is the IsRelative=0 that
seems to be what is needed make things work properly but I'd make the
rest match anyway, allowing for the file path differences on your system.
If you get this far your original PC should be able to access the Email
now directly from the server.
As for accessing the files from your other PC's all I can remember is to
first install Thunderbird on them but there was no need to actually
configure any Email or newsgroup accounts. Then from your "Main" PC
that you started with copy over the installs.ini and profiles.ini from
it over to the additional PC(s) and they should work. I just leave the
rest of the Thunderbird files alone on the various PC's as the
installs.ini and profiles.ini are all that is needed to redirect over to
the file server, providing you had Thunderbird already installed on the
various PC's.
There is one or two gotchas however, only one PC at a time can access
the files on the server as a lock file is created when you access the
Thunderbird from the server. Close out Thunderbird on the first machine
and then another machine can access them. The error messages you get
when the second or other PC's try to access the files makes it look like
Thunderbird crashed or something. I just force an exit on the PC that
can't access the files, go to the working one and close it. Then one of
the other PC's can access the file just fine.
The other problem is that if a copy of Thunderbird gets updated on a PC,
like usually happens automatically, and it then accesses the Email or
newsgroup files the remaining PC's won't be able to access the files
again until they also get upgraded to the same version of Thunderbird.
Also if a PC is accessing the Thunderbird files and crashes the lock
file is usually left behind on the server.
If that happens you may have to manually go to the Thunderbird profiles
folder on the server and delete the program called parent.lock. Once it
is deleted the other machines can then access the files once again. I
seem to vaguely remember the parent.lock being difficult to delete a
time or two as it would depend on which PC was trying to delete it or
else I had to use a file deleting program that was running on the server
itself. Try to delete it from the PC that crashed if possible as I
think that was the easiest most of the time.
Have fun and go slow.