MapiMessageMBS.kSendFlagDialog = 8

Type	Topic	Plugin	Version
const	Windows	MBS Win Plugin	18.5

One of the flags for SendMail.

Display a send note UI
A dialog box should be displayed to prompt the user for recipients and other sending options. When Dialog is false, at least one recipient must be specified.

MapiMessageMBS.kSendFlagLogonDialog = 1

Type	Topic	Plugin	Version
const	Windows	MBS Win Plugin	18.5

One of the flags for SendMail.

Display logon UI.
A dialog box should be displayed to prompt the user to log on if required. When the DisplayLogonDialog is false, the client application does not display a logon dialog box and returns an error value if the user is not logged on. SendMail ignores this flag if the MessageID parameter is empty.

MapiMessageMBS.kSendFlagNewSession = 2

Type	Topic	Plugin	Version
const	Windows	MBS Win Plugin	18.5

One of the flags for SendMail.

Don't use shared session
Create a new session.