If you see error 0x800F0954 when installing .NET Framework using Optional features in Windows 11/10, here's what you need to do to fix the issue.

Windows Server 2008 x64, two of them in fact in an NLB cluster. Trying to install .NET Framework 4, first went fine, second refuses. Running installation package - both the web installer and full ...

This will install the .NET package on your system. You should be connected to the internet while enabling the .NET Framework using Windows Features.

Needless to say I was mistaken and had to spent the entire weekend hunting for a solution on how to install the .Net 3.5 framework on my Windows 8 box.