How long do backup tapes last?

We use sony SDX3-100c backup tapes in a Sony Tape Drive
The rotation scheme we use is Monday - Thursday tapes and five Friday tapes (each friday of the month). Naturally the Monday through Thursday tapes get a lot of use. Can anyone tell me how long they use the tapes for? Lately we have had a lot of issues with the backup and the tapes are only about 4 months old. The tapes are expensive and we are a non-profit so we have been replacing the tapes once a year. What do other non-profits do? Thanks,

Most tape backup drives require cleaning from time to time, so make sure that is not the source of the issues you mention.

You may want to consider taking your friday tapes when it's their turn to be over-written and swap them with the daily tapes. This will give some of your daily tapes a much-deserved "vacation".

Also, you may need to do a complete format of your tapes to try and resolve any problems with them.

And lasty, just about every backup tape that I have ever seen comes with a lifetime warranty. If you format a tape and still have problems related to that tape (and not the drive) then you should be able to send it to the manufaturer and get a replacement.

Thanks, maybe we do just have a bad tape, I did clean the heads and that didn't seem to help.