Default button settings
vbDefaultButton1 0 The first button is default
vbDefaultButton2 256 The second button is default
vbDefaultButton3 512 The third button is default
vbDefaultButton4 768 The fourth button is default
Message box modality
vbApplicationModal 0 The user must respond to the message before continuing to work in the current application.
vbSystemModal 4096 On Win16 systems, this constant is used to prevent the user from interacting with any other window until he or she dismisses the message box. On Win32 systems, this constant works like the vbApplicationModal constant (see above) with the following exception: The message box always remains on top of any other programs you may have running.
Other MsgBox display settings
vbMsgBoxHelpButton 16384 Adds the Help button to the message box
vbMsgBoxSetForeground 65536 Specifies the message box window as the foreground window
vbMsgBoxRight 524288 Text is right aligned
vbMsgBoxRtlReading 1048576 Text appears as right-to-left reading on Hebrew and Arabic systems
MsgBox "How are you?", vbOKOnly + vbApplicationModal, "Application Modal"