Event ID 51 Disk warnings on devices that are not plugged in RRS feed

  • Question

  • I have a server that throws hundreds of Event ID 51 at the end of most system state backups, examples are:

    - An error was detected on device \Device\Harddisk2\DR67 during a paging operation.

    - An error was detected on device \Device\Harddisk3\DR68 during a paging operation.

    Unfortunately Harddisk2 and Harddisk3 do not exist on the system! In Disk Management I have Disk 0 which is partitioned into C, D and H drives, there is also a Tandberg RDX USB device (tape) attached internally which shows up as Disk 1. There was an external USB drive plugged in showing as Disk 2 but that hasn't been plugged in for two weeks and still the errors are present.

    There are no hardware errors showing in the LSI MegaRAID software which only looks after Disk 0 anyway.

    Does anyone know why I'm getting errors for devices that are not plugged in?

    Friday, February 14, 2014 9:35 AM

All replies

  • What backup software are you using?

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    Oscar Virot

    Monday, February 17, 2014 1:24 AM
  • Hi,

    Will the issue occur when you manually perform a system state backup?

    If not, I assume the issue occurs in a scheduled backup task. Check if any non-existent device is added in that backup task.

    If it persists when manually performing a system state backup, please go to Device Manager, click View - Show Hidden Devices, go to Disk Drives and uninstall all hidden disks.

    Also check the key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum and see if any non-existent devices are listed as subkeys specific following keys:



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    Monday, February 17, 2014 2:20 AM
  • I'm using Windows Backup.
    Monday, February 17, 2014 8:36 AM
  • Hi, 

    The scheduled task backup runs a script that calls a Windows system state backup, running this manually doesn't cause any errors - when it runs at it's scheduled it throws all the errors right at the end, there is nothing else running at this time. 

    The backup takes system state and puts it on a different partition of the same disk (disk 0). No other drives are referenced. The USB drive is connected in each day to copy the backups off but has not been plugged in for a couple of weeks, still the errors persist.

    I will check the registry as you suggest.



    Monday, February 17, 2014 9:02 AM
  • How are thing going? Please let us know if there is any progress.

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    Wednesday, February 19, 2014 4:31 AM
  • Hi,

    I have found two devices that are not plugged in at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\USBSTOR and removed them however I expect they'll be added back in when the drives are reconnected next week!

    So far no more errors.

    Wednesday, February 19, 2014 8:25 AM
  • There were no hidden disks.

    I have removed two USB drives from the registry that were not plugged in.

    I'm still getting warnings although fewer of them - 'An error was detected on device \Device\Harddisk3\DR86 during a paging operation.'

    These warning s appeared on Friday evening with the server not touched since Wednesday. There is no Disk3 in the system.

    Monday, February 24, 2014 8:17 AM
  • Check what are the devices are displaying at below registry path.


    I would recommend you to use USB Hub to connect two different USB drives from server,

    Instead of connecting directly to server.

    Manjunath Sullad

    Monday, February 24, 2014 9:07 AM
  • Hi, I have checked the registry path you mention (please see previous updates).
    Monday, February 24, 2014 10:40 AM
  •  It will reoccur in registry key. If the issue is gone with the key, let's see if issue will also back with it.  

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    Thursday, February 27, 2014 8:01 AM
  • Hi, The issue is still present after removing the registry entries although it looks like the 'DR' bit at the end has started from scratch:

    An error was detected on device \Device\Harddisk2\DR6 during a paging operation.

    Thursday, February 27, 2014 8:28 AM
  • When this error occurs during execution of a system state backup, it may reference a non-existent drive (it seems the system state backup creates a temporary virtual drive during its operation).  I've had success resolving this issue by simply deleting the WindowsImageBackup folder (the destination folder for the system state backups) and then subsequently executing a system state backup job, which creates the WindowsImageBackup folder anew.
    Monday, June 4, 2018 3:11 PM