Migrating maildirs to new computer

[Dan Davison]

I have a functioning setup on one computer with maildirs served by
dovecot, using nnimap in gnus. How should I migrate these maildirs to
a new computer? I have tried various combinations of the following,
but am always encountering problems (gnus says articles don't exist,
articles don't match their entry in the summary buffer, the number of
articles in a group doesn't match the number of files on disk, etc
etc). Things I have tried:

- copy maildirs across using rsync -aH
- restart dovecot server with sudo pkill -HUP dovecot
- tried both copying ~/.newsrc*, and also starting without
- tried deleting all the dovecot* files in the maildirs, and also
keeping them
- killing groups and then resubscribing

I don't really care about keeping marks and stuff like that. I'd be
happy to start completely from scratch, as though gnus and dovecot had
never previously encountered my maildirs, but even blowing away all
the ~/.newsrc* and dovecot* doesn't seem to work -- are there some
other files involved, or does the problematic information reside in
the file names / permissions of the actual emails?

Thanks a lot,

Dan