Udo's Techblog

This is very basic, but when I wrote this entry about being unable to reformat a new USB drive, it reminded me of an episode that happened as I was waiting at the Saturn Electro service desk because my printer had crapped out on me. As the unfriendly support guy was busy in the back with my printer (making up excuses why I couldn't return it), a woman came to the counter with her MacBook and a USB drive she just bought. We were bored, so we started chatting about her problem. Turns out, she couldn't copy folders from her laptop's drive to the USB disk - can you guess why?

Some USB drives are factory-formatted with NTFS, the Windows NT filesystem. By default, a Mac can read the disk just fine, but it can't write any data to it. A little pen icon with a strike through it indicates this read-only state on the Finder window's footer bar.

What you need to do is re-formatting the USB disk with a Mac-compatible filesystem. Don't be scared, open Disk Utility, click on the USB disk > select the Erase tab > select "Mac OS Extended (Journaled)" > click "Apply" to format (at which point any data currently on the disk will of course be erased).

All done!

Oh, and if it doesn't work, look at this here.