I changed the administrator password and now none of scheduled tape backups are working on any of my servers. All was working prior to the password change. What am I missing??

The backup jobs may store a username and password to use to enable them to access the files (I know ArcServe certainly does) - if the username/password used was the admin account, you'll need to go through each of the jobs and change the passwords on them.

Rgds
AndyF