wd 3tb harddrive only shows 800gb

BDAqua...

I guess you were right about the enclosure. I sort of suspected that but didn't want it to be true. Shelled out another $80 for a NewerTech HDD dock (model Voyager Q) plugged in the "offending" hard drive and voila! All working well now.

Still have issues with another drive I have - an external USB-connected 2TB HD. Copying larger files is generating lots of errors. The errors message tells me that the original file is corrupted, but I know that's not true. After hours of frustration I tested a 3rd-party utility called File Buddy which not only copied everything smoothly but also a lot faster. I have read that I might also have success using the terminal and cp command. I will try this next time.

Anyway, just wanted to say thank you.

Terminal copy command seemed to work a lot faster. Everything started out well... I watched it transfer about 80GB before I walked away. Eventually, though, this aslo failed. Ended up with the target drive spinning endlessly/uselessly and a target folder with zero bytes.

I don't think this is a Mac issue. Seems more like something to do with the 2TB iOmega drive. This issue started suddenly after moving the drive from where it sat for more than 1 year. Wondering now about cables... did I maybe swap with another drive?... is the cable critical?

Going to test a cable swap and see what happens...

BDAqua,

I hit solved on your last comment because I think you were right about my initial question.

I'm still testing. It goes slowly because I do a lot of work on the machine and don't want to conduct large file copy tests while using the computer for other things... every time a copy goes badly, I end up restarting the mac.

The cable swap did nothing... but weirdly, I swapped which USB socket on my mac I used and had the first successful transfer of a large file since I initially moved the drives. I'll be doing another large file transfer tonight or tomorrow and if that one works well, then it is either the usb port or some intermittent problem in the drive itself.

I did read somewhere that this drive needs to be plugged directly into a computer, not linked via a hub. So maybe somehow one of the usb ports on the mac is not as good as the other. Sounds sketchy, but we'll see.

Thanks for the help on this.

Well, for now at least, my problems seem to be over.

Copied close to 100GB to the drive last night... took a little over one hour (which is the speed I'd expect) and all went flawlessly.

My whole system is working really well since I was forced to spend time tidying up every little detail, so my curiosity ends here.

I won't be doing any more testing until/unless some other problems arise.

Thanks again for your help and suggestions. I will refer back to this conversation if things go sideways.