No such user as string-- cron entries not created

Cause

A file exists in /var/spool/cron/crontabs for the specified user, but this user is not in /etc/passwd or the NIS passwd(4) map. The system cannot create cron(1M) entries for nonexistent users.

Action

To eliminate this message at boot time, remove the cron file for the nonexistent user, or rename it if the user's login name has changed. If this is a valid user, create an appropriate password entry for this name.