When executing the Print Task when the Map is displaying multiple services and one of them is a cached ArcGIS Server Local service, the following error message is displayed:
"The following errors occurred while rendering the map image:
MapResourceItem0: Unable to connect to server."
This issue applies to Web applications built with the 9.3 Service Pack 1 version of the ArcGIS Server Web ADF for the Microsoft .NET Framework.
This is a known issue.