Can't initialize HDD (write protected)

[synce]

I bought a 3TB Caviar Green that I put it an old enclosure which only supported 2TB partitions. I initialized it anyway then remembered I had a newer enclosure which might support 3TB. So I put the drive in the new enclosure and I see the full 3TB but I can't initialize the drive again ("this media is write protected"). I can still use it normally in the 2TB enclosure however.

I've tried wiping and formatting using Partition Master, uninstalling the driver, and using different USB ports but nothing seems to work. The drive doesn't appear in DiskPart and there's no storagedeviceplicy registry entry that I can see (Win7). What's going on here?

Update: I managed to use DiskPart's 'clean' function on the 2TB enclosure, and it's no longer listed as GPT volume, but I still get the writed protected error on the 3TB.

 

[synce]

Thanks but I've tried all of that... Whether it's unallocated space or an active partition it appears as write protected in the 3TB enclosure.

I also tried another old 2TB enclosure and it seems to work fine in that one. It's driving me nuts

 

[synce]

Looks like it's WD's crappy USB board to blame. Their old ones worked just fine with various drives but I guess they're doing something different now. I hooked up the 3TB Green to one of my PCs thru SATA and had no problems initializing and formatting it to 3TB. I unplug it, hook it back up to WD's latest enclosure and we're back to square one. So I guess I gotta buy another one

 

[tomatthe]

WD seem to be completely obnoxious on things like that, the fact you can't use any of their non RE line on a consistent basis in a raid 5 / 6 set is ridiculous. They could be likened to apple for doing mess like what you mentioned.