Using a Mac drive on a PC
Sep 3, 2015, 3:33 pm
#1
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Using a Mac drive on a PC
So I was cruising craigslist yesterday, idly searching for computer parts I could use. I ran across a guy selling a half-dozen hard drives (desktop and laptop), including a couple of 500 Gb and one Tb. Under 10 bucks apiece. So I contacted him and drove down to pick them up. Sorry eBay; no shipping, no waiting (and also no guarantee, but I knew where he lived 
).
When I got back home, I used one of those gizmos that attach to a hard drive and allow you to connect it to a USB port. Well, Windows recognized the gizmo all right, but there seemed to be nothing attached to it - My Computer and Disk Management could see nothing.
I tried that with a couple of the other drives, with the same result. Uh oh. But wait - maybe the gizmo is bad - wouldn't surprise me. So I opened up the desktop and found a spare SATA connector and power feed and booted it up. Checking the bios showed that, indeed, there was a 500 Gb drive connected. Swell. Up comes Windows ... and no drive. It's like it's not even there. Hmmm. Instead of a cheap pile of hard drives, did I just buy an expensive pile of bricks?
.
And then ..."@:-)" ... Wait a minute! I recall that when I was in his office getting the drives, I saw a Mac on his desk, and a Mac laptop. I'll bet these are Mac drives.
A quick google check shows that they are probably formatted HFS, and I believe Windows does not (natively) support HFS. There are some utilities out there to read HFS, but I wasn't interested in reading the files, just getting at the disks.
After a little more coffee and some cogitating, I had an idea. I've done a lot of installs recently, so I dug out a Windows install CD (it was XP SP3, but it doesn't matter). I booted up the CD (with the new drive still attached) and once Windows had done its preliminary file loading, it asked me whether I wanted to do a repair or a clean install. I selected a clean install. It then showed me possible places, including my current drive, and a 500 Gb blob of "unknown partition". I selected the blob and then selected "Delete". It warned me of all the bad things that can happen when you delete a partition (yeah, yeah, yeah ... those are the bad things I want to happen) and said go ahead.
It now shows me a list of places, including a 500 Gb blob of "unpartitioned space". I selected it again and said "Create a partition", which it did.
I now had a partition that Windows could see!
Remove the CD, re-boot into Windows, and there's my drive. Made it an NTFS partition and formatted it. I don't know much about HFS (nothing, actually) but I know a 'quick format' just resets the indices, etc. and doesn't touch the bulk of the disk. Since I wasn't sure what HFS might leave out there, I decided to do a full format. Took well over an hour, but I was in business.
Once I had the procedure, I did the rest of them (I let the TB drive format overnight). Chkdsk showed them all to be 100% working order, no bad sectors, etc.
Now ... this all may be something everyone knows, but I didn't, and there may be others out there who don't know either.
Also, I can see situations where you might have a chance to pick up a nice Mac drive but when you try to use it, you'll be stumped like I was. Now you know what to do.
).When I got back home, I used one of those gizmos that attach to a hard drive and allow you to connect it to a USB port. Well, Windows recognized the gizmo all right, but there seemed to be nothing attached to it - My Computer and Disk Management could see nothing.
I tried that with a couple of the other drives, with the same result. Uh oh. But wait - maybe the gizmo is bad - wouldn't surprise me. So I opened up the desktop and found a spare SATA connector and power feed and booted it up. Checking the bios showed that, indeed, there was a 500 Gb drive connected. Swell. Up comes Windows ... and no drive. It's like it's not even there. Hmmm. Instead of a cheap pile of hard drives, did I just buy an expensive pile of bricks?
.And then ..."@:-)" ... Wait a minute! I recall that when I was in his office getting the drives, I saw a Mac on his desk, and a Mac laptop. I'll bet these are Mac drives.
A quick google check shows that they are probably formatted HFS, and I believe Windows does not (natively) support HFS. There are some utilities out there to read HFS, but I wasn't interested in reading the files, just getting at the disks.
After a little more coffee and some cogitating, I had an idea. I've done a lot of installs recently, so I dug out a Windows install CD (it was XP SP3, but it doesn't matter). I booted up the CD (with the new drive still attached) and once Windows had done its preliminary file loading, it asked me whether I wanted to do a repair or a clean install. I selected a clean install. It then showed me possible places, including my current drive, and a 500 Gb blob of "unknown partition". I selected the blob and then selected "Delete". It warned me of all the bad things that can happen when you delete a partition (yeah, yeah, yeah ... those are the bad things I want to happen) and said go ahead.
It now shows me a list of places, including a 500 Gb blob of "unpartitioned space". I selected it again and said "Create a partition", which it did.
I now had a partition that Windows could see!
Remove the CD, re-boot into Windows, and there's my drive. Made it an NTFS partition and formatted it. I don't know much about HFS (nothing, actually) but I know a 'quick format' just resets the indices, etc. and doesn't touch the bulk of the disk. Since I wasn't sure what HFS might leave out there, I decided to do a full format. Took well over an hour, but I was in business.
Once I had the procedure, I did the rest of them (I let the TB drive format overnight
). Chkdsk showed them all to be 100% working order, no bad sectors, etc.Now ... this all may be something everyone knows, but I didn't, and there may be others out there who don't know either.
Also, I can see situations where you might have a chance to pick up a nice Mac drive but when you try to use it, you'll be stumped like I was. Now you know what to do.
Sep 6, 2015, 8:18 pm
#2
Join Date: Nov 2000
Location: Upcountry Maui, HI
Posts: 13,305
you didn't have to boot an install CD, IIRC, you do it in disk management in windows, you have to reformat the entire drive, including, I believe, the label, so you have to partition it first. (assuming you aren't trying this on really super-old versions of windows.)
If it has an EFI (GPT) label, modern versions of windows should recognize it, but the article suggests that macs might use a hidden partition which you'd want to delete. I'd just wipe the entire thing and create a new label first. I'm guessing you just want one partition on it. IIRC, you can do all that in disk management, once it's done there, windows should see it.
IIRC you still use ancient versions of windows .. is that why you couldn't do this? Don't format it with an EFI label if you want to use an ancient version of windows or a really old computer that doesn't understand EFI labels. In that case you need the old MBR label, which is somewhat limited these days, at least for disk and partition size, number of partitions on a disk and which partitions can be used for booting if the disk is too big. (2TB I think, wow, this is ancient history these days.)
Here's an article that mentions the disk management tool, but also has some extraneous info for you about backing it up first. http://www.howtogeek.com/195530/how-...windows-drive/
Quick format would have been fine, it just lays out the new filesystem on the partition you are formatting. All the other blocks are unused and free or spare, and their data is unused. They will get overwrittten when they get allocated.
Older hw with BIOS probably won't recognize a GPT label. UEFI firmware will recognize it. That's probably why in your case MBR makes sense if the drive fits within it and you want to use it as a boot drive. Windows will recognize GPT on older computers if it's not a boot drive I believe. Not sure which version though.
-David
If it has an EFI (GPT) label, modern versions of windows should recognize it, but the article suggests that macs might use a hidden partition which you'd want to delete. I'd just wipe the entire thing and create a new label first. I'm guessing you just want one partition on it. IIRC, you can do all that in disk management, once it's done there, windows should see it.
IIRC you still use ancient versions of windows .. is that why you couldn't do this? Don't format it with an EFI label if you want to use an ancient version of windows or a really old computer that doesn't understand EFI labels. In that case you need the old MBR label, which is somewhat limited these days, at least for disk and partition size, number of partitions on a disk and which partitions can be used for booting if the disk is too big. (2TB I think, wow, this is ancient history these days.)
Here's an article that mentions the disk management tool, but also has some extraneous info for you about backing it up first. http://www.howtogeek.com/195530/how-...windows-drive/
Quick format would have been fine, it just lays out the new filesystem on the partition you are formatting. All the other blocks are unused and free or spare, and their data is unused. They will get overwrittten when they get allocated.
Older hw with BIOS probably won't recognize a GPT label. UEFI firmware will recognize it. That's probably why in your case MBR makes sense if the drive fits within it and you want to use it as a boot drive. Windows will recognize GPT on older computers if it's not a boot drive I believe. Not sure which version though.
-David
Last edited by LIH Prem; Sep 6, 2015 at 8:36 pm
Sep 6, 2015, 8:45 pm
#3
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I'm not sure what an EFI label is. I was using Windows 7.
Disk Management couldn't even recognize that the disk was there; otherwise of course I would have wiped it (this ain't my first rodeo). I had no idea what was on the drive, nor did I care. It was just an extra drive I could use, provided I could get at it.
I don't know why Windows couldn't see it, yet the XP install CD could. It doesn't matter - if I hadn't used that, I could very well have spent hours (on top of the time I did spend) getting information that was interesting but not useful to the problem at hand.
At the end of the day. it took 5 minutes to destroy the old/create a new partition and that was the end of it.
I'm sure it's not the only way to do this, but it's quick and effective. If it saves someone else hours of head-scratching and frustration, well, that's why I posted it.
Disk Management couldn't even recognize that the disk was there; otherwise of course I would have wiped it (this ain't my first rodeo
). I had no idea what was on the drive, nor did I care. It was just an extra drive I could use, provided I could get at it.I don't know why Windows couldn't see it, yet the XP install CD could. It doesn't matter - if I hadn't used that, I could very well have spent hours (on top of the time I did spend) getting information that was interesting but not useful to the problem at hand.
At the end of the day. it took 5 minutes to destroy the old/create a new partition and that was the end of it.
I'm sure it's not the only way to do this, but it's quick and effective. If it saves someone else hours of head-scratching and frustration, well, that's why I posted it.
Sep 6, 2015, 8:52 pm
#4
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There's an even better explanation/procedure here.
I'm sure it works, and I think I had run across this first. However, both procedures involve a lot more work than boot-select-delete-create. More than one way to skin a cat.
I'm sure it works, and I think I had run across this first. However, both procedures involve a lot more work than boot-select-delete-create. More than one way to skin a cat.
Sep 6, 2015, 9:01 pm
#5
Join Date: Nov 2000
Location: Upcountry Maui, HI
Posts: 13,305
There's an even better explanation/procedure here.
I'm sure it works, and I think I had run across this first. However, both procedures involve a lot more work than boot-select-delete-create. More than one way to skin a cat.
I'm sure it works, and I think I had run across this first. However, both procedures involve a lot more work than boot-select-delete-create. More than one way to skin a cat.
Was the disk not even visible in diskmgmt?
GPT is the GUID based partition table, used by UEFI and other firmware. New computers all come with UEFI these days, a replacement for the old BIOS. Modern versions of Windows, including 7, understand and can create GPT labels. (not sure if it was there from the beginning of 7 or not.)
People (including me) mistakenly call it the EFI label, because EFI uses it and may have had a part in defining it, but the correct term is the GPT label.
The old MBR label used by BIOS had size and other limitations that required a replacement as disks grew over the last decade. BIOS wasn't the only firmware with those limitations, the industry had to adapt and the GUID based partition table was adopted by most of the industry. It puts a fake MBR in block 0 that makes it look like the entire disk is allocated so if you plug the disk into an old computer that doesn't understand GPT, the disk will appear to be full with a single type EE partition, IIRC. You can, of course re-label it with a new MBR at that point, wiping out the rest of the disk.
-David
Last edited by LIH Prem; Sep 6, 2015 at 9:10 pm