The CAVI "vdc" account password should never expire and should not be auto-locked. There are several cron jobs that run behind the scenes which require the vdc account credentials. If the account password expires and gets locked, the cron jobs cannot run and may cause problems to the CAVI system. As an example, clearmon9.sh is a cron job that is run by the vdc account. Its function is to purge obsolete monitor data. If the script is not able to run, /opt/VDC/ directory will continue to fill up with the unwanted data until it is full. This will eventually result in the inability to access the 2d or 3d client.