1.
dism.exe /online /enable-feature /featurename:NetFX3 /Source:D:sourcessxs /all
2.
Start the Local Group Policy Editor or Group Policy Management Console.
Expand Computer Configuration, expand Administrative Templates, and then select System.
Open the Specify settings for optional component installation and component repair Group Policy setting, and then select Enabled.
Select the Contact Windows Update directly to download repair content instead of Windows Server Update Services (WSUS) check box.
3.
Create a folder under root (C:NetFx3 for example)
Copy the microsoft-windows-netfx3-ondemand-package.cab from a Windows install disk .sourcessxs to the C:NetFx3 folder
Command Prompt as an administrator
DISM.exe /online /enable-feature /featurename:NetFX3 /All /Source:C:NetFX3 /LimitAccess
The text progress bar will go to 100% when completed and will give you a message: "The operation completed successfully".
4.
有外国大牛写的standalone的安装包，需要的留下邮箱。
5.
dism.exe /online /all /enable-feature /featurename:NetFX3ServerFeatures /Source:d:sourcessxs /LimitAccess
dism.exe /online /all /enable-feature /featurename:NetFX3 /Source:d:sourcessxs /LimitAccess