Starting with Windows 11 Insider Preview Build 27965 and the upcoming 26H1 update, Microsoft is transitioning .NET Framework 3.5 away from being a "Feature on Demand".
The .cab file version does not match your specific Windows build number, or the path specified in the command line is misspelled. microsoft windows netfx3 ondemand package.cab download free
You should see:
Note: Change E: to match the exact letter of your virtual or physical Windows installation drive. Method 2: Installing from a Staged CAB File Location Starting with Windows 11 Insider Preview Build 27965