1. Mount DVD-install disc of Windows 10 to you computer or if you have ISO file, you can double click to mount to virtual device. in my case, I'm using DVD.
2. After that, run CMD as administrator, by press Windows + X then press A or Search for CMD... Right Click and Run As Administrator.
3. Write or copy-paste these code in CMD then press enter: Dism /online /enable-feature /featurename:NetFx3 /All /Source:X:\sources\sxs /LimitAccess
replace X with latter of DVD or virtual device.
in my case: Dism /online /enable-feature /featurename:NetFx3 /All /Source:E:\sources\sxs /LimitAccess
4. Now you Enable .Net Framework 3.5 SP1 or if not installed, now you can install Net Framework 3.5 SP1.
5. Or try easy way with .bat - Download: [Install .Net Framework 3.5 [Win10] (DSMI).bat]
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