Can't Mount NTFS Partition!

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Level 5

5,090 points

Can't Mount NTFS Partition!

I'm having trouble mounting an NTFS partition that was formatted using a Windows installer. When I head to the Terminal, I type "diskutil list" to get a listing of my current volumes and their partitions.

I see this:
/dev/disk0
#: type name size identifier
0: GUID partitionscheme *93.2 GB disk0
1: EFI 200.0 MB disk0s1
2: Apple_HFS MacBook HD 62.0 GB disk0s2
3: Microsoft Basic Data 30.8 GB disk0s3

So you can see that Disk Utility sees the slice with the NT File System just fine. This is also shown in the GUI as well. However, this slice is greyed out on left sidebar.

Next, I create a subdirectory in the /Volumes directory using the mkdir utility as follows: "mkdir /Volumes/Windows".

Finally, I try to mount the partition using the mount_ntfs utility using the following syntax: "sudo mount_ntfs /dev/disk0s3 /Volumes/Windows". However, I get this output: "mount_ntfs: /dev/disk0s3: Invalid argument".

Can anyone help me? It feels like there's something wrong with the GPT (or MBR??) more so than a badly formatted filesystem because of the fact that I can boot into this partition and use Windows just fine (and have been for a while), but Mac OS X just won't mount it!

Can someone help? This is driving me crazy!

MacBook w/ 1GB RAM, 100GB HD, Mac OS X (10.4.9), iPod Video

Posted on Apr 30, 2007 5:36 PM

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Answer 1

Best reply

Jun T.

Level 4

2,185 points

May 1, 2007 11:58 AM in response to Brian Reading

Are you sure the partition is NTFS? Isn't it FAT32?
Did you modify the partition table which BootCamp set up?
Anyway, Windows partition are usually automatically mounted, so something seems to be wrong with your disk, but I don't know what it is...

It feels like there's something wrong with the GPT (or MBR??)

You can see GPT and MBR partition talbles by

sudo gpt -r show disk0

sudo fdisk /dev/rdisk0

(fdisk may show NTFS partition as FAT32)

In addition, the gpt command may issue a warning if it thinks that MBR is out of sync with GPT.

If you think MBR has problem and want to fix it, then you may try "Partition Inspector" in rEFIt. Download the diskimage, create a boot CD and boot your Mac from the CD (or you can install rEFIt into your Mac and reboot. See the documents), and select "Partition Inspector" from the boot menu. But be sure to have backups before doing this. And I'm not sure if this solves your problem...

PowerMacG4, PowerBookG4, iMac(C2D) Mac OS X (10.4.9)

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Answer 2

Brian Reading Author

Level 5

5,090 points

May 1, 2007 11:20 PM in response to Jun T.

Are you sure the partition is NTFS? Isn't it FAT32?

Yes. Very sure. It was formatted using Windows Vista's Installer which won't even let you use FAT32 I believe.

Did you modify the partition table which BootCamp set up?

Not particularly, but it's possible that Windows Vista's Installer did.

>sudo gpt -r show disk0
gpt show: /dev/disk0: Suspicious MBR at sector 0 gpt show: error: bogus map gpt show: unable to open device '/dev/disk0': No such file or directory

>sudo fdisk /dev/rdisk0
Disk: /dev/rdisk0 geometry: 12161/255/63 [195371568 sectors] Signature: 0xAA55 Starting Ending #: id cyl hd sec - cyl hd sec [ start - size] ------------------------------------------------------------------------ 1: EE 0 0 2 - 25 127 14 [ 1 - 409639] <Unknown ID> 2: AF 25 127 15 - 1023 21 6 [ 409640 - 130023424] HFS+ *3: 07 1023 254 63 - 1023 254 63 [ 130435072 - 64933888] HPFS/QNX/AUX 4: 00 0 0 0 - 0 0 0 [ 0 - 0] unused

If you think MBR has problem and want to fix it, then you may try "Partition >Inspector" in rEFIt.

Good idea! I didn't know this utility existed. I ran it, and got this:
* Report for internal hard disk * Current GPT partition table: # Start LBA End LBA Type 1 40 409639 EFI System (FAT) 2 409640 130433063 Mac OS X HFS+ 3 130695208 195371527 Basic Data Current MBR partition table: # A Start LBA End LBA Type 1 1 409639 ee EFI Protective 2 409640 130433063 af Mac OS X HFS+ 3 * 130435072 195368959 07 NTFS/HPFS MBR contents: Boot Code: Unknown, but bootable Partition at LBA 40: Boot Code: None (Non-system disk message) File System: FAT32 Listed in GPT as partition 1, type EFI System (FAT) Partition at LBA 409640: Boot Code: None File System: HFS Extended (HFS+) Listed in GPT as partition 2, type Mac OS X HFS+ Listed in MBR as partition 2, type af Mac OS X HFS+ Partition at LBA 130695208: Boot Code: None File System: Unknown Listed in GPT as partition 3, type Basic Data Partition at LBA 130435072: Boot Code: Windows BOOTMGR (Vista) File System: NTFS Listed in MBR as partition 3, type 07 NTFS/HPFS, active
See anything unusual? Thanks for your help! So far, out of everyone on the web, you've been the most helpful!

Brian

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Answer 3

Bill Scott

Level 6

11,459 points

May 1, 2007 11:36 PM in response to Brian Reading

You emailed everyone on the web?

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Answer 4

Brian Reading Author

Level 5

5,090 points

May 2, 2007 12:55 AM in response to Bill Scott

One time... :P

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Answer 5

Jun T.

Level 4

2,185 points

May 2, 2007 3:57 AM in response to Brian Reading

Hi Brian,

gpt show: error: bogus map

bogus map!? gpt command thinks GPT itself is broken?

But according to Partition Inspector, GPT's notion of the partition may look like the following:
<pre>
# Start Size Type
0 1 MBR
1 1 Primary GPT header
2 32 Primary GPT table
(a) 34 6 (unused)
1 40 409,600 EFI System (200MB)
2 409,640 130,023,424 HFS+ (62GB)
(f) 130,433,064 262,144 (unused) (128MB)
3 130,695,208 64,676,320 Basic Data (30.48GB)
(b) 195,371,528 7 (unused)
195,371,535 32 Secondary GPT table
195,371,567 1 Secondary GPT header</pre>
(1 block = 512 bytes; see http://developer.apple.com/technotes/tn2006/tn2166.html for more info.)
I think this is a standard partition created by BootCamp. Apple wants to align every partion at 4KB boundary (8 block boundary), so are the gaps (a)(b). Apple also wants to create a 128MB free space (f) between partitions.

But MBR's notion of the partition is different:
<pre>
# Start Size Type
0 1 MBR
1 1 409,639 EFI protective(ee)
2 409,640 130,023,424 HFS+(af) (62GB)
130,433,064 2,008 (unused)
3 130,435,072 64,933,888 NTFS(07) (30.96GB)
195,368,960 2,608 (unused)</pre>
EFI protective (#1) indicates this portion is resereved for EFI and should not be modified. So this is OK. Partition#2 is identical to GPT's #2. But the Windows partition (#3) has different position and size than in GPT. This is very bad. (I don't know what caused this problem; did you use BootCamp1.2, which is the first version supporting Vista?)

I think rEFIt's gptsync ("Partition Tool") can modify MBR so that it is in sync with GPT. But this is usefull only before you install Windows (or Linux, etc.). Since you have already installed Vista (and using it), modifying MBR will break Vista which uses only MBR.

If it is OK for you that you can not mount Windows partition onto MacOS, then you may continue to use current GPT/MBR... It may not break either MacOS or Windows, bacause the two partitions do not overlap... But I'm not sure.

I strongly recommend you to backup your data in both MacOS and Vista. Then you may use rEFIt to correct MBR, and re-install Vista.
Or start BootCamp assistant and see whether it offers an option to delete the Windows partition and bring the disk back into a single HFS+ volume. If it does, delete the Windows partition, re-create a Windows partition, and you can re-install Vista.

Or start over from a clean install of Tiger (and then install Vista).

If you prefer to walk on a tight rope and try to manually modify GPT so that it is in sync with MBR, then you may try
gpt remove -i 3 disk0
gpt add -b 130435072 -s 64933888 -t windows disk0
but I'm not sure this will work or not; it may destroy everything (both MacOS and Vista) so you need backups anyway. If you want to modify GPT manually, you need to boot from Tiger install DVD, and I guess it would be better to boot into a single user mode; this means hold down C-key to boot from DVD, and if booting from DVD starts, then hold down command-S for single user mode. If gpt complains that the device disk0 is busy, then unmount it by "diskutil unmount disk0s2".
But, even if this works, it will leave GPT in a state different from that set up by BootCamp, so BootCamp can not undo it (it can not bring your disk back into single MacOS partition). I recommend to re-install (at least) Vista if you want to sleep well.

Good luck!

PowerMacG4, PowerBookG4, iMac(C2D) Mac OS X (10.4.9)

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Answer 6

Bill Scott

Level 6

11,459 points

May 2, 2007 9:28 AM in response to Brian Reading

This one is completely out of my league. I think when people don't answer, it is because they don't know how to answer (at least in my case), not that we don't admire the problem.

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Answer 7

Brian Reading Author

Level 5

5,090 points

May 2, 2007 11:28 AM in response to Jun T.

Jun,

Thanks! I thought it was odd that rEFIt found two separate entries for the GPT partition and MBR partition, while the others didn't have this. I wasn't sure if this was standard behavior for this sort of filesystem/partition configuration though, so it's good that you were around to help for this.

It looks like the moral of the story here is: "Don't let Windows format your partition!". Apparently, it doesn't know how to work with the GPT/MBR hybrid (or at least not all the time).

I'm going to try backing up my data in Windows Vista, restoring the partition back to a single HFS+ partition with Boot Camp's utility (if it lets me), re-partition it again with Boot Camp, then re-install Vista. All the while, I'll make sure to keep checking if everything is alright in the partition tables. This will have to wait a little while though, I need to study for two final exams coming up in a few days. :P

Thanks for your help Jun! Although this was something I was fearing, at least I know how to recognize a problem like this in the future.

Brian

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Answer 8

Brian Reading Author

Level 5

5,090 points

May 2, 2007 11:26 AM in response to Bill Scott

This one is completely out of my league. I think when
people don't answer, it is because they don't know
how to answer (at least in my case), not that we
don't admire the problem.

I hear ya Bill. I was stumped pretty good myself.

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Answer 9

Brian Reading Author

Level 5

5,090 points

May 8, 2007 11:22 AM in response to Brian Reading

Just to follow up, I have everything working fine now in OS X. In Boot Camp Utility, I restored my volume to one partition easily. However, while attempting to repartition, the Boot Camp Utility was unable to do so. I had to boot from my Mac OS X Install Disc, run Disk Utility, and repair the volume for Boot Camp to work correctly again.

However, like I mentioned, after the Windows Vista reinstall, everything mounts fine in Mac OS X.

Brian

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Answer 10

michaK

Level 1

0 points

May 8, 2007 3:25 PM in response to Brian Reading

Hi Brian,
I tracked your solution for this problem from the bsdforums.org

I have the exact same problem on my MBP, just with a smaller NTFS-partition...

So could you please tell me exactly what I need to do now?
Do I need to attempt the repartitioning by the Bootcamp-Assistant or can I directly repair the volume from my Install Disk?

I really don't want to take any risk right now, as I'm in the middle of writing my bachelor thesis (as it always comes down to these occasions...). I have backups but I don't really have time to do a reinstall of Mac OS...

Anyways, I can't say how glad I am I found this topic. It seems we are the only two people who have that problem or at least want to do something about it...
So thank you Brian and especially Jun!

Greetings from Germany,
Michael

MBP 1.1 Mac OS X (10.4.9) Bootcamp with Vista Business

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Answer 11

Brian Reading Author

Level 5

5,090 points

May 13, 2007 12:44 PM in response to michaK

You'll need to restore the Volume to one partition using the Boot Camp Assistant, then boot from your OS X Install Disk, and repair the disk. Then, repartition with Boot Camp Assistant, and re-install Windows.

Anyways, I can't say how glad I am I found this
topic. It seems we are the only two people who have
that problem or at least want to do something about
it...
So thank you Brian and especially Jun!

Yeah, I was amazed that I couldn't really find much information on the web about this. Jun's the real hero!

Brian

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