Procedure to Repair Windows Update.
This procedure should fix Windows Update that has been broken due to a virus.

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Unregister Windows Update Server Files
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1. First of all close all instances of Internet Explorer.
2. Click Start and Run, type CMD and in the command window type the following commands:
Regsvr32 /u jscript.dll
Regsvr32 /u wuaueng.dll
Regsvr32 /u wuaueng1.dll
Regsvr32 /u wucltui.dll
Regsvr32 /u wups.dll
Regsvr32 /u wuweb.dll
Regsvr32 /u wuapi.dll

Once these files are unregistered successfully restart the system and now let us register the following files using the Regsvr32 command and check whether the issue is resolved. Please note, there is a space between Regsvr32 and the file name.

Reregister Windows Update Service Files
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1. Close all instances of Internet Explorer.
2. Click Start and Run, type CMD and in the command window type the following commands:
Regsvr32 wuapi.dll
Regsvr32 wuaueng.dll
Regsvr32 wuaueng1.dll
Regsvr32 wucltui.dll
Regsvr32 wups.dll
Regsvr32 wuweb.dll
Regsvr32 jscript.dll
Regsvr32 atl.dll  (NOTE: Please register this file only do not attempt to unregister this file)

Restart and now try to use Windows Update
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