Does anyone know how to programmatically set the "Mark Complete" flag in Exchange 2007 which makes a check mark appear in outlook. In outlook you can right click and select the "Mark Complete" option. I want to achieve this programmatically based on some conditions. Any ideas on how to do this would be greatly appreciated.
You have to use the ExtendedPropertyDefinition class:
ExtendedPropertyDefinition epd_PidTagFlagCompleteTime = new ExtendedPropertyDefinition(0x1091, MapiPropertyType.SystemTime); msg.SetExtendedProperty(epd_PidTagFlagCompleteTime, DateAndTime.Now);