My LTO Tape Drive says 'C' in the front and won't allow me to continue backups.

The 'C' in the front of the drive means that the drive needs to be cleaned. 

- If you have a cleaning tape, you will need to run the tape at least twice in the drive.  The cleaning tape will self eject each time it is finished.

- If you do not have a cleaning tape on hand, you will need to purchase one.  An online retailer like Amazon will carry these tapes. 

- Cleaning tapes are generally universal.  Most cleaning tapes will have a life span of about 50 uses.

- If you have a library that states that the drive needs to be cleaned, you will need to load one of the slots with the cleaning tape and manually move it to the drive to clean.  *Depending on manufacturer, you may need to manually move the tape back.  The Platform UI will not recognize the cleaning tape but the tape drive should.