NTBackup Error: Invalid Command

[CA1286080]

Hi,

I have this strange error when i use NTBackup with SBS 2003:

The device reported an error on a request to write data to media.
Error reported: Invalid command. There may be a hardware or media problem. Please check the system event log for relevant failures.

I have requested the hotfix named in Microsoft KB article 817688. But i can't apply this hotfix because newer version is on the system. I have already installed SP1 for W2003 server and SBS 2003 Server. But KB 817688 is not in SP1 solved issues list. Another issue with Shadow copy should be fixed in SP1 according to list. My HP Storageworks DAT 40 tapestreamer works ok with Tapeware program coming with streamer. I would like to use NTbackup because of online backup function for Exchange. I'm out of clues at the moment.

Any help would be appreciated!

Thanks in advance.

Jan Spruit