I use a USB docking device and swap drives frequently. Every time I swap I must go into Disk Manager and rerereassign the same drive letter. Surely this isn't normal. How do I stop this behavior?
Normally when you first connect a drive windows writes a hidden signature to it so it knows the disk it could be it hasnt written this check to see if the have them but take care How to Change the Disk Signature of a Drive Without Losing Existing Data or Reformatting (howtohaven.com)
Thanks for your reply.
How would I look to see if it has written this thing to the disk?
The article you reference says it's for people who get this error message:
"This disk is offline because it has a signature collision with another disk".
I don't get an error message
Also, these drives have been connected many times and contain data
The article tells you how to view the signature to see if its there and different on both drive
I only copied the ID of the changeable disk that is currently installed.
Disk ID: {64328230-4C18-4012-9503-7069F9998BC3}
Is that the kind of number I should have expected?
The other two disks are internal disks and the IDs are different. The C: drive looks much like the ID above with different characters. The other I use to store data is only a simple 8 characters
Last edited by iamjim; 18 May 2018 at 20:29.
You are giving false information. This has nothing to do with the problem he/she has. Obviously, both disks are Online so there is no disk signature collision. What causes signature collision is when you clone one disk to another in which case the disk signature also cloned to the other disk then Windows will put the cloned disk Offline. Each disk has a unique disk ID and Windows does not mess with it except checking to make sure its signature is unique with other disk(s).
@iamjim
For each partition/volume within a disk, Windows assign a unique Volume GUID as a mount point. Open Admin command prompt and type:
mountvol
You'll get a list of mount points for each partition/volume and the letter assigned to each. System Reserved/EFI System/Recovery partition will have no MOUNT POINT (No letter assigned).
You can also view these mount points from the Resgistry under:
HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices
Here's a list of mounted devices in my PC as an example:
Here's my suggestion:
Delete everything under this key. Reboot the PC and let Windows re-assign new mount points for each volume/partittion.
If still does not work:
Back up your data from the troubled disk, use diskpart to re-initialize it. From Admin Command:
diskpart
select disk 2
clean
create partittion primary
format fs=ntfs quick
exit
Then restore your data to this disk.
I agree with topgundcp. It is definitely not a "unique ID" problem.
There are two possibilities. ( may be more, which I don't know )
1. Somehow automount got disabled .
2. All drive letters have been locked with Windows "forgetting" to release the drive letters when drives are removed. ( Instead of editing the registry manually as suggested by topgundcp, I would prefer an easier and safe method of doing it with drivecleanup.
So let us move on.
1. Check whether automount is disabled and enable it if it is disabled.
Start > All Programs > Accessories > Right click on Command Prompt and Run as administrator.
Then
diskpart [ENTER]
Against the DISKPART prompt
automount [ENTER]
Does it say "automatic mounting of new volumes disabled" ? Then
automount enable [ENTER]
"automatic mounting of new volumes enabled"
Close Command Window.
Done.
2. Instead of manually editing registry, use this tiny elegant drive utility "drivecleanup" to remove all registry entries and drive letters pertaining to non-present devices.
Download v 0.8.1 of the drivecleanup.zip from https://www.uwe-sieber.de/drivetools_e.html (Roll down on this page till you see DriveCleanup V 1.5 )
(Note: You can use the latest version V1.5.0 too. I have been using v 0.8.1 since long regularly)
Unzip it to a folder, say drivecleanup.
You will have two folders Win32 and x64 each containing DriveCleanup.exe for 32 bit and 64 bit respectively.
Remove all USB storage devices from your system (except your Keyboard and mouse) and reboot. Disconnect internet/network.
Right click on the DriveCleanup.exe and run as administrator. (Use the DriveCleanup.exe file appropriate for your bit version of Windows.).
After the clean up act, reboot and check whether the drive letter you want is available.
( When you plug in your USB devices after this cleanup, these will be installed afresh. What you have done is to remove all non-present devices and drive letters associated with them and start with a clean slate. Hopefully that should resolve the problem.)
it says automatic mounting is enabled
Given that, are all the other steps needed?
If automount is enabled you need not do anything further on it. Close command window and then try #2 drivecleanup
There's nothing unsafe about removing all mount points and let Windows start out fresh.2. Instead of manually editing registry, use this tiny elegant drive utility "drivecleanup" to remove all registry entries and drive letters pertaining to non-present devices.
Download v 0.8.1 of the drivecleanup.zip from https://www.uwe-sieber.de/drivetools_e.html (Roll down on this page till you see DriveCleanup V 1.5 )
Same as you, I also use DriveCleanup V.1.2 but it only removes the orphan devices, not all devices including devices with mount points which I suggested:
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