wsus Registry
Computer\HKLM\Software\Policies\Microsoft\Windows\WindowsUpdate

.NET 3.5 on W2012R2

Mount the W2012R2 installer in the DVD drive (below coommand assumes its on the D drive)

DISM /Image:C:\test\offline /Enable-Feature /FeatureName:NetFx3 /All /LimitAccess /Source:D:\sources\sxs

https://technet.microsoft.com/en-us/library/dn482069.aspx