Question : Problem: how to make 4mm dds4 cartridge be read only

I've used 4mm dds for over a year, and just now discovered it doesn't work the way I thought.

I always thought the little white slider on back of the tape worked like a 3.5" floppy disk.

It is simple right? "Slide it to the left, and the tape is read only, slide it to the right and it is update."

WRONG. If I slide it to the right, NTBACKUP handles everything fine.

But, if I slide it to the left, NTBACKUP under SBS 2003 does not recognized the cartridge.  Instead, NTBACKUP says
"Unrecognized media has been found in location “ARCHIVE Python 06408-XXX SCSI Sequential Device”.  This media may have never been used, or may contain information generated by an incompatible program.  Do you want to prepare this media for use with Backup?  Warning: This will erase any data currently on the media."  

What the heck does the slider do?

Answer : Problem: how to make 4mm dds4 cartridge be read only

It is the write-protect switch.

I've checked on Microsoft's support site and this doen't appear to be a known bug. I'm wondering if you've got a bad drive. You might like to e-mail Certance support  (they don't have a knowledgebase) at http://www.certance.com/about/contact/ContactTechnicalSupport to see if they've seen this before, because something certainly isn't right.