GetError
The GetError function gets a description of the
last error that occurred.
Syntax
Important: This feature is deprecated, and may be removed
in a future version.
CALL ui.Interface.frontCall("WinMail","GetError",
  [ id ], [ result ] )
- id is the message identifier.
 - result is the description of the last error.
 - the returned value is NULL if there was no error.