Do you use the Debian dspam packages, specifically with one of the database backends? Recently upgraded the packages? Does noone email you anymore?
You might be bitten by a bug, or perhaps undocumented misfeature, that bit me this morning. No emails were coming in and yet the mailserver logs said they were coming in, but a closer look at the logs showed this:
Aug 15 09:08:17 elmo dspam: dlopen() failed: /usr/lib/dspam/libpgsql_drv.so: /usr/lib/dspam/libpgsql_drv.so: cannot open shared object file: No such file or directory
What happened here? A quick look at the installed packages said the pgsql backend was still installed but this file was not being found.
The latest version of libdspam7-drv-pgsql now has multiarch support which means
/usr/lib/dspam no longer exists and the driver is found in
/usr/lib/x86_64-linux-gnu/dspam. The problem happens because the configuration file specifies the directory and that has now changed. The fix is as simple, update /etc/dspam/dspam.conf with the new path.