Windows Windows Server

How to Fix “Unknown hard error” on Windows Server and Windows 10


This error “Unknown Hard Error” is usually associated with Windows Server and Windows 10 operating systems. It is an error that is related to the explorer.exe file, sihost.exe file, ctfmon.exe, and other .exe files. It is one frustrating and critical error that can freeze your system and stop any process on your computer system. Some people have complained that whenever this error pops up, they experience problems like a blank screen, frozen taskbar, blank desktop, in summary they are not allowed to do anything, sometimes briefly while sometimes it takes a long period. Despite all these, this issue can still be fixed if you follow the troubleshooting steps below.

For more related Windows Operating System errors you can read this: How to Fix “Insufficient System Resources Exist to Complete the Requested Service” error, How to fix the issue “The Security Database on the Server does not have a Computer Account for this Workstation Trust Relationship” on Windows Server [Part 2], How to Quickly Fix Windows Search Bar Not Working, Windows Out Of Box Experience: OOBESETTINGSMULTIPLEPAGE error on Windows 10, Windows cannot connect to the printer: Operation Failed with error 0x000004f8

Windows Server
Error display

The following are some of the causes of this error:

  • It can be caused by explorer.exe, sihost.exe, ctfmon.exe, or other .exe files.
  • A corrupted system file or registry entries in the OS can cause it.
  • Malware attack or Virus infection on the system.
  • A recent Windows update on the system.

Follow these troubleshooting steps to fix the “Unknown Hard Error”

  • Perform a clean boot of the system

Sometimes performing a clean boot of the system will fix this issue. Just type msconfig in the Run and hit Enter.

Click on Services and check the box Hide all Microsoft Services and click on Disable all and click Ok.

Windows 10
Msconfiguration Panel
  • Now click on the Startup tab and click on Open Task Manager.
  • Select each Startup item and click Disable and Ok when done.
  • Reboot the computer.
Hard error
Startup Panel

After these few steps, you can confirm if the issue is resolved. You can start enabling the services one after another to detect which service is causing the error. If it’s an installed update you can revert back to the previous state.

Using CHKDSK command for your Hard drive State

This kind of error can also show if your hard drive is failing. However, You can use CHKDSK command to remove any of this possible error:

Open your Command Prompt as an administrator and enter the below command


it depends on what letter is attached to your hard drive. This command utility will scan the whole hard drive for errors and try to fix any errors on it.

CHKDSK Command
  • Run DISM Command

To fix “Unknown Hard Error” on Windows Server, employ the DISM (Deployment Image Servicing and Management) command. This method effectively addresses issues caused by corrupt or lost files, providing a reliable fix for the error.

Open your Command Prompt as an administrator and enter the below command

DISM.exe /Online /Cleanup-image /Cleanup-image /Restorehealth

I trust you found the contents of this article detailing the resolution steps fix “Unknown hard error” on Windows Server both informative and valuable. Should you require further clarification or have inquiries, please feel free to post them in the comments section below.

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