Help!!! - Zip Disk Ejecting

My zip disk keeps ejecting. I have an external 250MB zip drive for my MPC 2000. Every time I put the disk in the drive it ejects it and doesnt even give it a chance to read. What to do to fix this?

try unpluging eveything for like 10 minutes then re try it that might help......it may need to reset its self.......did you buy it used or new?

tried other disks?

Where you able to read those disks b4 ? A 750Mb disk will eject when you insert it in a 250Mb zip drive.