I'm trying to get this to work
Install-WindowsFeature NET-Framework-Core -source \\unc\blah\software\
I'm specifying a path that directly contains dotnetfx35.exe and I've tried specifying the path to the file and to the containing folder but neither works. I suspect there is some kind of folder structure I need to put in place but I can't find any documentation. This might be better on Server Fault but since I'm trying to install a framework using code I thought I'd try here first
You can't give it an installer .exe file; that's not how this cmdlet works. It's looking for files in the side by side (SxS) of the local computer first. The path you give it has to be to a similar SxS store. You can also mount a WIM and point it at that.
From Install-WindowsFeature on MSDN:
Personally, I don't think it's worth hosting this somewhere internally. If you're using WSUS and are trying to workaround the problem where client machines try to download dot net 3.5 from WSUS (where it doesn't exist), then I recommend using group policy to set the policy listed above in
3)
to allow clients to download .NET 3.5 directly from Windows Update. That has been working fine for me.