External drive letters changing



  • I have a server with only 2 USB ports. OS is Windows Server 2016 STD.

    Since I need more than that to plug in external usb drives I purchased a USB powered hub.

    It's been working fine for a long time, however just recently after a reboot the drive letters are changing from what they are manually assigned in Disk Management and even the name of the volume is changing.

    I have read about clearing the drive attributes in diskpart and also the possibility of the server now detecting the USB hub as a new device each time.

    Has anyone worked on this issue before and what did you do to resolve it?


  • Service Provider

    I would assume the USB drivers were updated and caused windows to think they were "new" or something.



  • @JaredBusch said in External drive letters changing:

    I would assume the USB drivers were updated and caused windows to think they were "new" or something.

    Yes, I agree. But even after I 'correct' it, they are still changing.



  • I presume that the drive letters are changing because the volume name is changing. The system sees a new drive, so you get a new letter.



  • @CCWTech said in External drive letters changing:

    I have a server with only 2 USB ports. OS is Windows Server 2016 STD.

    Since I need more than that to plug in external usb drives I purchased a USB powered hub.

    It's been working fine for a long time, however just recently after a reboot the drive letters are changing from what they are manually assigned in Disk Management and even the name of the volume is changing.

    I have read about clearing the drive attributes in diskpart and also the possibility of the server now detecting the USB hub as a new device each time.

    Has anyone worked on this issue before and what did you do to resolve it?

    Are you properly ejecting the USB drives before taking them out? I think sometimes they don't fully clear and then you have a letter conflict. I'm not 100% sure on this though..



  • @Reid-Cooper said in External drive letters changing:

    I presume that the drive letters are changing because the volume name is changing. The system sees a new drive, so you get a new letter.

    Not sure why the volume name changes though.



  • @dave247 said in External drive letters changing:

    @CCWTech said in External drive letters changing:

    I have a server with only 2 USB ports. OS is Windows Server 2016 STD.

    Since I need more than that to plug in external usb drives I purchased a USB powered hub.

    It's been working fine for a long time, however just recently after a reboot the drive letters are changing from what they are manually assigned in Disk Management and even the name of the volume is changing.

    I have read about clearing the drive attributes in diskpart and also the possibility of the server now detecting the USB hub as a new device each time.

    Has anyone worked on this issue before and what did you do to resolve it?

    Are you properly ejecting the USB drives before taking them out? I think sometimes they don't fully clear and then you have a letter conflict. I'm not 100% sure on this though..

    Not removing them at all. Just after a reboot.



  • @CCWTech said in External drive letters changing:

    @dave247 said in External drive letters changing:

    @CCWTech said in External drive letters changing:

    I have a server with only 2 USB ports. OS is Windows Server 2016 STD.

    Since I need more than that to plug in external usb drives I purchased a USB powered hub.

    It's been working fine for a long time, however just recently after a reboot the drive letters are changing from what they are manually assigned in Disk Management and even the name of the volume is changing.

    I have read about clearing the drive attributes in diskpart and also the possibility of the server now detecting the USB hub as a new device each time.

    Has anyone worked on this issue before and what did you do to resolve it?

    Are you properly ejecting the USB drives before taking them out? I think sometimes they don't fully clear and then you have a letter conflict. I'm not 100% sure on this though..

    Not removing them at all. Just after a reboot.

    Oh, that is much worse.



  • Rower85 said to do this...

    Open Run and type "Diskpart"
    type "LIST VOLUME"
    note witch volume number that you want to autoassign on boot

    Create a textfile on C:\ named: diskpart.txt
    Put this in the textfile:
    select volume "drive number"
    assign letter="drive letter to assign"
    (in the " " brackets, input your stuff, also you do not need the "")

    Open Run and type notepad
    Put this in:
    diskpart /s c:/diskpart.txt
    click File > Save As...
    locate C:\ and change File Name to "diskpart.bat" then change Save as type: to All Files and press Save

    Now go to Task Scheduler in the Admin section on the Control panel.
    Make a new folder in the "Windows" sub folder named "Diskpart"
    rightclick the "Diskpart" folder
    click "Create Basic Task..."
    name it to "Diskpart" and click "Next >"
    select "When the computer starts" click "Next >"
    select "Start a program" click "Next >"
    click "Browse..."
    select the "Diskpart.bat" file you saved on C:, click "Next >"
    select "Open the Properties dialog for this task when I click Finish" click "Finish"
    Properties should come up, now select "Run with highest privileges"
    click "OK"



  • @Reid-Cooper said in External drive letters changing:

    Rower85 said to do this...

    Open Run and type "Diskpart"
    type "LIST VOLUME"
    note witch volume number that you want to autoassign on boot

    Create a textfile on C:\ named: diskpart.txt
    Put this in the textfile:
    select volume "drive number"
    assign letter="drive letter to assign"
    (in the " " brackets, input your stuff, also you do not need the "")

    Open Run and type notepad
    Put this in:
    diskpart /s c:/diskpart.txt
    click File > Save As...
    locate C:\ and change File Name to "diskpart.bat" then change Save as type: to All Files and press Save

    Now go to Task Scheduler in the Admin section on the Control panel.
    Make a new folder in the "Windows" sub folder named "Diskpart"
    rightclick the "Diskpart" folder
    click "Create Basic Task..."
    name it to "Diskpart" and click "Next >"
    select "When the computer starts" click "Next >"
    select "Start a program" click "Next >"
    click "Browse..."
    select the "Diskpart.bat" file you saved on C:, click "Next >"
    select "Open the Properties dialog for this task when I click Finish" click "Finish"
    Properties should come up, now select "Run with highest privileges"
    click "OK"

    Problem is that the volume names are changing as well.



  • @CCWTech Maybe it is time for eSATA 🙂



  • I dealt with this while I was still carrying disks home weekly for our backup processes.

    The issue for us was just a simple change drive letter (for both drives) since they automatically mounted and we're assigned a litter that didn't work with our backup solution.

    While a manual process, it worked.



  • @CCWTech As an alternative, you can try this tool: https://www.uwe-sieber.de/usbdlm_e.html