Error functions display error messages and prompt the user for a response. Following are the error functions:
| Function | Description |
| FlashWindow | Flashes the window by inverting its active or inactive state. |
| MessageBeep | Generates a beep on the system speaker. |
| MessageBox | Creates a window with the given text and title. |
For detailed information about error functions, see the Microsoft Windows Programmer's Reference, Volume 2.