Formatting Problems with a My Book 1TB

I just got a My Book Essential Edition 1TB external hard drive.

It came formatted for Windows with a FAT32 filesystem but as I’m on OS X I wanted to repartition and change the filesystem to Mac OS Extended (Journaled). Should be easy enough using Disk Utility but it just kept bitching about some error:

“The underlying task reported failure on exit.”

Useless. No information as to what actually went wrong. Looking in the system.log (/var/log/system.log) more information was revealed.

Disk Utility[587]: newfs_hfs: /dev/rdisk1s1: partition size not a multiple of 4K.

So by changing the partitions to be a multiple of 4K everything now works.

2008/Aug/14 at 18:33


2008-10-21 05:06

david van brink

Wow, thank you for this morsel of USEFUL INFORMATION! I just got home from the Santa Cruz Costco with a new MyBook 1tb ($185, I love living in the future) and had the same problem. Disk-utility Partition tab did the trick. Domo domo domo.

2009-05-08 18:28


Shit. Yea, my Mac Pro OS 10.5.6 wizbang version of Disk Utility has the same “feature” and doesn’t deal with this problem gracefully.

2011-03-30 21:28


One question. After we partition My Book, can WD SmartWare still able to detect it properly?

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