If you are having trouble with the AT (Schedule Service) command, it might be because the Schedule Service is running under the default System account context, which has no network access. To Access network drives, add net use commands with an appropriate user account as in net use Drive: \\Server\Share password /U:UserId

I recommend setting up a user account (ROBOT) that is a member of the Domain Admin group. This account should have a non-blank, non-expiring password. Grant it the permissions required. Give it all the User Rights and Advanced User Rights that you would ever require of a batch job. In Control Panel / Services / Schedule, configure startup to use this account. Stop and Start the schedule service.

If the job requires interaction with the desktop, you will need the /Interactive switch. This may require using the System account.
Debug your batch job by adding ECHO and Pause commands to the batch. Schedule AT time /interactive "cmd.exe /k" and run the job from the window it opens. This should let you see what is happening within the context of the schedule service account.

Get a good scheduler! I sell OpalisRobot, an event based scheduler for Windows NT. Events are:

date/time
file creation
directory size limit
event log entry
success or failure of a task
SQL query
ODBC Query
State of a service
Interactive event

Based on one or more linked events, tasks can be triggered:

Batch or executable
Command execution
SQl file or Query
Action on an NT Serviice
Shutdown
Remote execution
File Copy or move
Directory copy
File Print
Send Mail or message
ODBC query or data xfer
RAS connect or hangup
Send Event Log message