You can display error messages to users from inside a script
without using APIs. For example, you can display an error message
for users to see in the Assets application when an asset number does
not follow the rules for naming assets.
Error messages created with automation scripts
To post error messages, you set the predefined errorgroup implicit
variable and the predefined errorkey implicit variable
to the error message group and error key. You can also post error
messages by using the MXException class in the
API.