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i am trying to query the physical sector size of my drive using fsutil:

C:\Windows\system32>fsutil fsinfo ntfsinfo c:
NTFS Volume Serial Number :       0x78cc11b2cc116c1e
Version :                         3.1
Number Sectors :                  0x000000003a382fff
Total Clusters :                  0x00000000074705ff
Free Clusters  :                  0x00000000022fc29b
Total Reserved :                  0x00000000000007d0
Bytes Per Sector  :               512
Bytes Per Physical Sector :       <Not Supported>
Bytes Per Cluster :               4096
Bytes Per FileRecord Segment    : 1024
Clusters Per FileRecord Segment : 0
Mft Valid Data Length :           0x00000000305c0000
Mft Start Lcn  :                  0x00000000000c0000
Mft2 Start Lcn :                  0x0000000003a382ff
Mft Zone Start :                  0x0000000006951940
Mft Zone End   :                  0x0000000006951c80
RM Identifier:        19B22CBE-570D-19DE-9C72-CD758F800DDC

You can see that the Bytes Per Physical Sector value is Not Supported:

Bytes Per Physical Sector :       <Not Supported>

In the KB Article Microsoft support policy for 4K sector hard drives in Windows, Microsoft says:

  • If fsutil.exe continues to display "Bytes Per Physical Sector : <Not Supported>" after you apply the latest storage driver and the required hotfixes, make sure that the following registry path exists:

    HKLM\CurrentControlSet\Services\<miniport’s service name>\Parameters\Device\
          Name: EnableQueryAccessAlignment
          Type: REG_DWORD
          Value: 1: Enable

The only thing i don't know is what my Miniport's service name is.

What is my miniport's service name.

i know that my SATA drives are in AHCI mode, and AHCI uses the msahci driver service:

enter image description here

Is that my miniport service? "MSAHCI"?

Bonus Chatter

The following script can detect if your partitions are not correctly aligned on a 4,096 byte boundary:


Set objWMIService = GetObject("winmgmts:{impersonationLevel=impersonate}!\\.\root\cimv2")

Set colItems = objWMIService.ExecQuery("Select * from Win32_DiskPartition")

For Each objItem in ColItems
offset = (objitem.startingoffset / 4096)
If Clng(offset) = offset then
    wscript.echo  objitem.DeviceID & ": startingOffset=" & objitem.startingoffset & " is a multiple of 4,096 bytes. The partition IS aligned correctly."
    wscript.echo  objitem.DeviceID & ": startingOffset " & objitem.startingoffset & " is NOT a multiple of 4,096 bytes. The partition is NOT aligned correctly. (It's off by " & objitem.startingoffset Mod 4096 & " bytes)"
End If

Which is only important if you have an Advanced Format (i.e. 4,096 byte per sector) drive. If the drive was partitioned in Windows Vista SP1 or later then it will already be aligned correctly (Windows, starting with Vista SP1, understands AF drives). You can use an Hitachi tool to correct alignment issues if the drive was partitioned by Windows XP, or suffered PartitionMagic or a clone operation.

See also

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Were there any advancements? – Bort Jan 3 '13 at 18:11
@Bort Nope! &nbsp; – Ian Boyd Jan 3 '13 at 19:52

Maybe this is the key:

"DisplayName"="Microsoft USB Open Host Controller Miniport Driver"
share|improve this answer
What does this have to do with the question? – HopelessN00b Jun 22 '14 at 18:20
The orig question was: "What is my miniport's service name?" Looks like from my above, that the service name is "usbohci." – tomlancer Jun 22 '14 at 22:08
Did you not look at the 'bold' part of my answer? Here it is again: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\usbohci] – tomlancer Jun 22 '14 at 22:08
Now, that may vary slightly, but it should be pretty generic overall. – tomlancer Jun 22 '14 at 22:09
Or, you could reference the 'DisplayName' in my comment as well: "DisplayName"="Microsoft USB Open Host Controller Miniport Driver" - I hope that clears it up. And I hope it is helfpul. Thanks. – tomlancer Jun 22 '14 at 22:16

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