Fix
Please remove the following corrupted files from exim database and restart exim.
removed `/var/spool/exim/db/ratelimit’
removed `/var/spool/exim/db/ratelimit.lockfile’
removed `/var/spool/exim/db/retry’
removed `/var/spool/exim/db/retry.lockfile’
removed `/var/spool/exim/db/wait-dk_remote_smtp’
removed `/var/spool/exim/db/wait-dk_remote_smtp.lockfile’
removed `/var/spool/exim/db/wait-remote_smtp’
removed `/var/spool/exim/db/wait-remote_smtp.lockfile’
restarted exim