Issue Description
- Unable to install RSAT tool via Optional feature or DISM command
Cause
It is happening because windows 10 isn’t able to reach out to Microsoft update to install the feature.
Fix
– UseWUServer from 1 to 0 temporarily, Once your installation finished, change it back to 1 otherwise windows update will not work via your company’s SCCM server.
- restart windows update service.
Thanks for reading !
Learn Tech Future 
Bang on solution…Thanks for sharing brothers…
– Change value for Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU:”UseWUServer” key to 0
– Restart WindowsUpdate service
– Try installing the required capability using DISM cmd (in my case it was the active directory one)
– Change back the reg key to 0
– Restart WindowsUpdate service again
Perfect solution! Thanks much again.
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Correction on 4th step of my previous comment: Change back the ”UseWUServer” to 1
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