You must use the Role Management Tool to install or configure Microsoft. NET. Full write-up/walkthrough.
You can download the Windows Server 2012 trial version to get an ISO with the required source files. Mount the ISO with the inbox ISO mounting and run DISM to install. Net 3.5: dism.exe /online /enable-feature /featurename: Net FX3 / Source:d:\sources\sxs / Limit Access If it fails, also try to run this Update before trying to activate. Net 3.5: Update for the. NET Framework 3.5 on Windows 8, Windows 8.1, Windows Server 2012, and Windows Server 2012 R2 This removes 2 security updates which may prevent setup of. Net 3.5.
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