C# Error CS1672 – Invalid option ‘{0}’ for /platform; must be anycpu, x86, Itanium, arm, arm64 or x64

C# Error

CS1672 – Invalid option ‘{0}’ for /platform; must be anycpu, x86, Itanium, arm, arm64 or x64

Reason for the Error & Solution

Invalid option ‘option’ for /platform; must be anycpu, x86, Itanium or x64

The options specify the processor type; use one of the forms listed.