IMessage::CopyTo returns MAPI_E_NO_ACCESS if IMessage is opened from .msg file

When I try this with messages that are opened from a .msg file on disk and contain attachments, IMAPIProp::CopyTo returns 0x80070005 (MAPI_E_NO_ACCESS).

Standalone MSG files implementation has more bugs than a bait store. CopyTo also does not correctly remap named properties.

I always use my own implementation that calls GetPropList / SetProps excluding some properties, copies recipients, and processes attachments recursively (since they can contain embedded messages).