This weekend after an update to kernel-2.4.9-e.68 on my RHEL 2.1 mail server, Novell NetMail wouldn't start.  It gave the enlightening message "NetMail is already running", which of course it wasn't, since i had just rebooted (ps -ef confirmed this).

A quick strace /opt/novell/netmail/bin/ims revealed that it was looking at /var/opt/novell/netmail/ims.pid.  This file still had data in it from the last boot (i'm not sure why this would have been the case).  The pid in that file did exist, but was a completely different application (as might be expected after a reboot).  Removing the file allowed NetMail to start normally.

None of this is at all unusual, except that it appears that no one in the known universe has ever run into this problem before.  Searches on Google, Novell's support forums, and Novell's entire web site revealed no hits for the phrase "NetMail is already running".

Surely i can't be that weird.