The problem is in the Time Machine formatting of that drive. Once you ok’d Time Machine to use that drive for backups, it changes the drive from Windows-friendly FAT32 to a Mac-only format called Mac OS Extended. Time Machine sort of hijacks the drive and won’t let go until you reformat it as FAT32 and then tell Time Machine to bugger off.

If you wan the Time machine backups, which many people do, one thing you could do is format the drive in two partitions – one partition with about 300GB for Time Machine (you can even name the partition “TimeMachineBackups”) and the remaining 200GB for Windows/Mac transfers – FAT32 formatting, of course.

Once the partitions are created, allow Time Machine to capture the 300GB partition and the 200GB partition will be spared for other uses.

Jason

If the drive is formatted as NTFS, then you won’t be able to use it on your iMac without buying some software to make it compatible. Pain in the butt. If the drive is FAT32, then you’re all set. If it is NTFS, then my suggestion would be to get the drive onto a Windows machine and back up the existing data, then format it as FAT32, then move data back.

The quickest way to tell if the drive is FAT32 is to simply drag a file from your iMac to the drive. If it copies over, then you’re good. If it won’t copy or if it gives an error, then you probably have an NTFS drive and a simple fix.

Jason

I’have just bought a WD my passport (essencial) but it was a 8b8 is there anny possybility to put it in my mac book ? :s

I followed your instructions and was able to successfully remove the drive from my passport elite 500gb (R/N A7B).

I did break a couple of the clips, and if I had known more about the locking mechanism inside, I would’ve known that you want to pry the black section out and away from the grey, rather prying the grey up and away from the black (breaking clips in the process). Just in case you want to include it in your post.

Cheers,
Arya

Jason

According to an article at http://slickdeals.net/forums/showthread.php?sduid=0&t=1192095 if the drive is identified by “BBB” it has the updated USB port built-in. If it is identified as “A7B” or “B7B”, is should be usable within the context of this article. This identifier may be found on the exterior case of “My Passport” just after the S/N as the R/N.

Thanks for your work in putting this excellent tutorial together, Jason.

Definitely look for drives with 16MB cache or more. Generally speaking, those higher-cached drives are going to be much more responsive for basic computing tasks, and even for some hard-core operations like video editing, etc. Of course, 7,200RPM is going to be better than 5,400RPM. Typically battery life isn’t dramatically affected by a faster spinning drive – maybe a 10% reduction or so. If you can live with that, I’d go for a faster drive. If you still want to retain the most off-mains minutes, then stick to a 5,400RPM drive with as much cache as possible.

I hope that helps a little.

Jason

Thanks for the great instructions. Looking to change my 100Gb (toshiba mk1032gsx) drive for a larger one as it is full and can’t decide what drive to get. I had ordered a WD5000BEVT but I have just seen that it only has an 8Mb cache vs the 16Mb on that is in my machine now. Does this make a difference? I am not too fussed to move up to 7200rpm as I don’t want my machine to chew any more battery as it is pretty old already.

Any advice on what drive to choose? Thanks

Jason

I bought the Passport to rip it apart to put the HDD inside of my Wii actually (getting rid of the dvd drive… who uses those things these days?) and sadly it was all in one so going to take it back and buy an elite and I’ll let you know.

I’ll upload a picture here of the Passport Essential.

http://www.sockrocket.com/temp/passportBack.jpg
http://www.sockrocket.com/temp/passportFront.jpg