Error 0x800F081F while installing .NET Framework 3.5 on Windows 10
Error 0x800F081F while installing .NET Framework 3.5 on Windows 10 might be due to corporate WSUS servers not allowing such updates.
Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU in the Windows registry and set UseWUServer to 0 (zero). Restart the Windows Update service (net stop wuauserv & net start wuauserv) and retry installing .NET Framework 3.5. Set UseWUServer back to 1 (one) and restart the Windows Update service.
HUMENTH
Not working…
Trond Endrestøl
What didn’t work? Read the description more carefully. I had to follow these steps as recently as last week (2019/W45).