USB Drive Error

[jjykim]

I connected my USB drive to my macbook pro, but it doesn't show up. It's happened before.

Anyway, I went into Disk Utility to see if I could repair the disk, and I was greeted with this error message, which I have attached as a screenshot.

What could this mean?

 

[-aggie-]

Somehow your partition mapping got messed up. You'll need to reformat the drive. If you need to get data off before that, you'll need data recovery software.

https://forums.macrumors.com/showthread.php?p=10638168