I was having trouble with .net framework install on new computers. I'm not sure why it didn't work repeatedly, but found that if you pop a flash drive in with windows 11 on it, and use the following command it works.
C:\Windows\System32>DISM.exe /Online /Enable-Feature /FeatureName:"NetFx3" /All /LimitAccess /Source:"D:\sources\sxs"
