troubleshooting Question

USB Thumb Drive Won't Do HFS+ Format

Avatar of markbyrn
markbyrnFlag for United States of America asked on
Mac OS X
9 Comments2 Solutions1292 ViewsLast Modified:
I've been trying to format a 128 GB USB thumb drive as a Mac OS Extended volume (HFS+) but it silently fails and the only successful format I can do is MS-DOS FAT. As I want to use the drive to install a dev version of Lion, I need the HFS+ format and trying it in terminal gave the following result:

Marks-MacBook-Pro:~ markbyrn$ diskutil eraseDisk HFS+ lion disk1
Started erase on disk1
Unmounting disk
Creating the partition map
Waiting for the disks to reappear
Formatting disk1s2 as Mac OS Extended with name lion
Initialized /dev/rdisk1s2 as a 128 GB HFS Plus volume
Mounting disk
Could not mount disk1s2 with name (null) after erase
Finished erase on disk1
Marks-MacBook-Pro:~ markbyrn$

So it appears to initialize but won't mount. I also tried partioning the drive into 2 or 4 partitions and formatting an individual partition but that didn't work either.

I have installed the dev version (preview 2) of Lion on a 16 GB thumb drive but there's not enough free space to do an update to preview 3. Any advice on how I can get this 128 GB thumb drive formatted?

Our community of experts have been thoroughly vetted for their expertise and industry experience.

Join our community to see this answer!
Unlock 2 Answers and 9 Comments.
Start Free Trial
Learn from the best

Network and collaborate with thousands of CTOs, CISOs, and IT Pros rooting for you and your success.

Andrew Hancock - VMware vExpert
See if this solution works for you by signing up for a 7 day free trial.
Unlock 2 Answers and 9 Comments.
Try for 7 days

”The time we save is the biggest benefit of E-E to our team. What could take multiple guys 2 hours or more each to find is accessed in around 15 minutes on Experts Exchange.

-Mike Kapnisakis, Warner Bros