The VerifyErrorBox function, shown below, illustrates how to solve the problem of different error messages on each GUI platform. For example, if a GUI platform always adds the prefix "Error:" to its message, while the other platforms do not, you might use or create a GUI Specifier for that platform and then use the VerifyErrorBox function as follows:
VerifyErrorBox (STRING sMsg)
// verifies that the error box has the correct error
// message, then dismisses the error box
const ERROR_PREFIX = "ERROR: "
const ERROR_PREFIX_LEN = Len (ERROR_PREFIX)
STRING sActMsg = MessageBox.Message.GetText ()
// strip prefix "ERROR: " from GUI Specifier for that platform error messages
if (GetGUIType () == GUI Specifier for that platform)
sActMsg = SubStr (sActMsg, ERROR_PREFIX_LEN + 1)
Verify (sActMsg, sMsg)
MessageBox.Accept ()