MSU are the Microsoft Update files. 
You can easily install the MSU file silently without reboot with the following command line:


wusa.exe Windows6.1-KB123456-x86.msu /quiet /norestart

To Uninstall it Silently you need to follow this simple procedure:

1) Run this command:
expand c:\temp\Windows6.0-KB123456-x86.msu –F:Windows6.0-KB123456-x86.xml c:\temp

2) This will create an XML file in temp folder as per the name above.
Edit this xml in notepad.

3)Find the assemblyidentity tag. Then, note the values of the following attributes:

• The name attribute
• The publickeytoken attribute
• The processArchitecture attribute
• The version attribute

4) Use the below command to uninstall the MSU from your machine.
start /w pkgmgr /up:name~publickeytoken~processArchitecture~~version

Note: The variables above need to be replaced by the vaules you have copied in step 3.

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