I have a dedicated server that my hosting company today informed me they've received spam alerts from. I had an old installation of Elgg that I have now removed, but I was wondering if anyone knows of what steps I can take to investigate this further. Unfortunately I can't seem to locate my mail.log, but in a control panel (plesk) I have found a mail queue with a long list of failed emails. Some of them referenced the domain that had the Elgg installation, but lots of others just show MAILER-DAEMON@default-server-domain.com (default-server-domain here just references a default domain that came with the server).
A lot of these seem to be to the same address, I have googled the address but found nothing of interest. Does anyone know what else I can check to try and narrow this down? Or perhaps a way to create better logging (and/or move the logs to a new directory?)
If it helps I'm on Fedora