A few Days back , I was working on Installing SCORCH on Windows 2012 box . As a Prerequisite I had to Install .NEt Framework 3.5 on the server and While I tried to Install it using Server Manager it gave me Error Every time ( As Shown Below )

After a little thought process I found this Solution to the problem .
Enter the Windows 2012 Disc and then Enter the Following Command as an Admin ( You Might get an Error if you try to Execute the Command Using Normal User stating that Elevated User Rights are Required )
dism /online /enable-feature /featurename:NetFX3 /all /Source:drive Name :\sources\sxs /LimitAccess
The Drive Name should be the Name of the Drive where you Windows CD is :
After you execute the command :
Now , ON the Ass Server Roles Window Click on Specify an Alternate Source Path and then Enter the same path there (drive Name :\sources\sxs )
Install the .NET Framework 3.5 and the issue is solved .
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