How do I call .NET/C# code from X++?

X++ can call .NET types directly when the assembly/type is available.

System.Guid guid = System.Guid::NewGuid();

info(guid.ToString());

For your own .NET assembly, make sure the reference and deployment are correct.

If the .NET call can throw, handle CLR exceptions appropriately instead of assuming every failure will come through as Exception::Error.