If MySQL won’t start due to corrupt InnoDB tables, you can add
[mysqld]
innodb_force_recovery = 4
to the /etc/my.cnf file, and restart MySQL. This will allow MySQL to start even with the corrupt InnoDB tables. I’m not quite sure if this fixes the tables or merely allows MySQL to run despite the warnings.

More Info

Sometimes the files and directores in /var/spool/exim/scan do not get purged, which leads to the inability of the system to create new files and directories in this location.

1. Stop Exim
2. Move to /var/spool/exim/scan
3. Delete all files in above directory- ‘ls -l | xargs rm -rf’
4. Start Exim

Problem solved.