FIX: Error message when you use the UNLOAD and REWIND options to back up a database to a tape device in SQL Server 2005: "Operation on device '<TapeDevice>' exceeded retry count"
Source: Knowledge Base
Product: Microsoft SQL Server 2005 Enterprise Edition, SQL Server 2005 Standard Edition & SQL Server 2005 Enterprise X64 Edition
Notification Contents: New and Major Modifications
FIX: Error message when you use the UNLOAD and REWIND options to back up a database to a tape device in SQL Server 2005: "Operation on device '<TapeDevice>' exceeded retry count"
http://support.microsoft.com/kb/940379/en-US