ZIP 100 Problems

I just bought a brand new zip 100 disk for my MPC, but for some reason it's not working in my external zip that is connected to my computer.
It's keep telling me to insert the disk when it's already inserted.
This is a brand new fujifilm zip 100 IBM formatted disk.
My other used zip disk works flawless.
Anyone know what might be the problem?

Hang on........your new disk isn't working in the zip drive on your computer? Is it working ok in the MPC's zip drive?

Maybe try reformatting it on the MPC, save a few sounds & then see if the computer's drive reads anything now.

Are both zip drives 100MB models?