| Setting | Description | Visual Basic |
| Yes | A zero-length string is a valid entry. | True (–1) |
| No | (Default) A zero-length string is an invalid entry. | False (0) |
| AllowZeroLength | Required | User's action | Value stored |
| No | No | Presses ENTER Presses SPACEBAR Enters a zero-length string | Null Null (not allowed) |
| Yes | No | Presses ENTER Presses SPACEBAR Enters a zero-length string | Null Null Zero-length string |
| No | Yes | Presses ENTER Presses SPACEBAR Enters a zero-length string | (not allowed) (not allowed) (not allowed) |
| Yes | Yes | Presses ENTER Presses SPACEBAR Enters a zero-length string | (not allowed) Zero-length string Zero-length string |