One casualty of the move to new hardware is that the mailing list passwords are invalid.
The way to fix this is to go to Options -> Mail Utilities which is enter the mailing list name and then run the bin/changepw command.
To fix all the passwords, go to
Options -> Mail Utilities and enter *
for the list names. This will give you all the lists
and their passwords. If there are problems, look in
the Apache error_log or php.err.
Take the list names and passwords and put them in a file. Then copy ~www/php/mailman/changeallpw
to the bin directory version of mailman (e.g. mailman_2/bin) and update the script, changing mailman_N
appropriately.
Then run
cat /tmp/pw | bin/changeallpw > /tmp/pw2 sh /tmp/pw2