Below is the method to export installed windows patches in an html
For that open the command prompt by typing cmd in run
Command window will popup. Use the below commands to get the list of Windows OS patches
C:\Users\rac>cd %userprofile%
C:\Users\rac>wmic qfe list full /format:htable > hotfixes.htm
C:\Users\rac> start iexplore %userprofile%\hotfixes.htm
C:\Users\rac>
You will get an html file with list of patches opened