Windows could not search for new updates – Code 8024402C Windows Update encountered an unknown error

During a recent security scanning of our machines, we found several machines have not been updated for several months. These machines are running Windows 7 and set up to get updates automatically. Something was not right and caused the machine to stop receiving updates. I tried to do manually update on one computer and got this error message.

A quick search found this article which helps me to solve the problem. The problem of my machines were caused by a registry value. Here are the steps I used to fix it.

1. Click on the Windows logo on the task bar and type regedit.
2. Right click on the regedit.exe program and select Run as administrator.
3. Browser to this key:
   HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU
4. Double click on the value named UseWUServer and change the value data from 1 to 0. If you could not find this value or the value data is already 0, the cause of your problem is different. You’ll have to search for other solution.
   
5. We have to restart the Windows Update service. In a Windows Explorer window, locate Computer. Right click on it and select Manage.
6. Locate the Windows Update service. Right click on it and select Restart.
   

If restarting of the Windows Update service does not help, you can try to reboot the machine. I also found that after the registry change, one machine is still not able to do Windows Update correctly. I downloaded the Windows Update troubleshooter to fix that machine’s problem. Here is the link:

Open the Windows Update troubleshooter