Can you provide more detail of the Unknown error 0x80131604?

Our .NET Encryption wrapper uses a technique to encrypt the whole managed assembly, and create a native executable as the loader for license validation and assembly decryption. Using the Assembly class could cause a conflict because most of its methods need to access the assembly in run-time. But the assembly is encrypted, and return the exception error. In this case, you may consider using the KeyCheck API instead of the wrapper method.