From Xojo Documentation
| This item was deprecated in version 2019r2.
Please use SerialConnection.Error as a replacement.
| This event is only available on macOS and Windows platforms.
For cross-platform compatibility, use ＃If...＃Endif with the Target... specifiers to make sure you will not attempt to use this event on an incompatible platform.
Occurs when there is an error with the Serial control. Available on Windows and macOS.