If you come across such an error in login in CpanelSorry for the inconvenience!
The root partition on this server is running out of disk space. Cpanel operation temporarily suspended to prevent something bad from happening. Please ask your system admin to remove any files, not in use on that partition.
SOLUTION
make sure that your partition is not full
empty the /var/log or /backup/cpbackup/monthly
Read Also: How to Check Disk Space Usage from cPanel