The following table lists the trappable errors for the MSComm control.
| Constant | Value | Description |
| comInvalidPropertyValue | 380 | Invalid property value |
| comSetNotSupported | 383 | Property is read-only |
| comGetNotSupported | 394 | Property is read-only |
| comPortOpen | 8000 | Operation not valid while the port is opened |
| 8001 | Timeout value must be greater than zero | |
| comPortInvalid | 8002 | Invalid Port Number |
| 8003 | Property available only at run time | |
| 8004 | Property is read only at runtime | |
| comPortAlreadyOpen | 8005 | Port already open |
| 8006 | The device identifier is invalid or unsupported | |
| 8007 | The device's baud rate is unsupported | |
| 8008 | The specified byte size is invalid | |
| 8009 | The default parameters are in error | |
| 8010 | The hardware is not available (locked by another device) | |
| 8011 | The function cannot allocate the queues | |
| comNoOpen | 8012 | The device is not open |
| 8013 | The device is already open | |
| 8014 | Could not enable comm notification | |
| comSetCommStateFailed | 8015 | Could not set comm state |
| 8016 | Could not set comm event mask | |
| comPortNotOpen | 8018 | Operation valid only when the port is open |
| 8019 | Device busy | |
| comReadError | 8020 | Error reading comm device |
| comDCBError | 8021 | Internal error retrieving device control block for the port |