Convert RMAIL format mailbox to mbox format
From FaqWiki
Can I convert my RMAIL file to a regular mbox format file?
I used Emacs "rmail" to manipulate my incoming mail, and now I have a file "RMAIL" in my home directory which other mail readers do not seem to understand. Can I convert that file to the normal "mbox" mailbox format, so I can import the messages into other mail readers?
Assuming procmail is installed on your machine, a command of the following form should do the trick:
formail -B -s < emacs-RMAIL-filename > mbox-filename
formail should be located in /software/procmail/bin/formail.
The procmail package is, or can be, installed on most MFCF/CSCF-supported machines.
Many thanks to:
which provided the solution to this problem when I needed it.