I get this problem all the time with MHonarc 2.1. Have you seen it?
----- The following addresses had permanent fatal errors -----
|"cat - | /opt/local/bin/mhonarc -add -outdir
(expanded from: eng-archive(_at_)guinness(_dot_)digisle(_dot_)net)
----- Transcript of session follows -----
Trying to lock mail archive in
ERROR: Unable to create
/opt/ns-home/internal/htdocs/mis/mail-archives/eng/.mhonarc.lck after 10
Apparently a previous invocation of mhonarc aborted abnormally
and left the lock file. You will need to manually delete the file
to get things going again.
Also, do you have any utilities for rebuilding the threads.html and
maillist.html files if they become corrupted? I've seen the contrib stuff if
your .db is corrupted, but need to rebuild the other corrupted files. I trie
the mailing list without luck.
I must of missed your message.
Once the .db file is recreated, you can regenerated the index pages
by calling mhonarc with the -editidx option.