How to install .NET 3.5 offline using Windows ISO (Windows 8/8.1/2012/2012 R2)
First right click the ISO for the Windows install, and click mount. Open a command prompt as Administrator and run the command below, replacing “x” with the drive letter the Windows Install ISO was mounted to.
Dism /online /enable-feature /featurename:NetFx3 /All /Source:x:\sources\sxs /LimitAccess
Replace x:\ with the path to your installation media.
sample output:
C:\>Dism /online /enable-feature /featurename:NetFx3 /All /Source:g:\sources\sxs /LimitAccess
Deployment Image Servicing and Management tool
Version: 6.3.9600.16384Image Version: 6.3.9600.16384
Enabling feature(s)
[==========================100.0%==========================]
The operation completed successfully.
Restart Windows to complete this operation.
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