This error message is displayed when you specify an invalid name for a mapped object in the Object Name Mapping dialog. The specified mapping name will be used to address the object in scripts, so it must be a valid script identifier.
Scripting languages supported by TestComplete have different naming rules. A simple way to make a name suitable for any scripting language is to use only alphanumeric (A…Z, a…z, 0…9) or underscore ( _ ) characters in the name and start the name with a letter.