At random times throughout the day and night I get this error message:
Can not get status of directory, error message: Error Code: 87
Description: The parameter is incorrect.

Sometimes once a day, sometimes 3 or 4. Then one or more emails shortly after like:
DMS - Traversing directory "\\SERVER\SHARE" produced this error: Error Code: 87
Description: The parameter is incorrect.

Where "\\SERVER\SHARE" is the physical path on my network that apparently cannot be reached.

The "\\SERVER" is a NetApp Filer NAS/SAN connected by a rock solid 3 megabit WAN link (2xT1 bonded). It has snapshots backed up on it during the day at the local side of the device. However the above errors do not always match up with the backup schedule, so I do not think that the backup workload is causing an issue and no one is reporting any other access problems to the NetApp.

Thoughts? What additional information should I provide?

This is the latest version of watchDirectory running on Server 2003.

What monitoring method uses this task?
Does it perhaps help if you set it to "Polling"?