Similar issue in my DP 7.
When I launch the command from a DOS console, the reports is sent. But, when I use the graphical interface this report never works and the Software crash (I kill the graphical Interface with Task Manager)
This WORKS.
c:\>omnirpt -report list_sessions -timeframe 24 24 -html -smtp usuario@dominio.com
using Grapical interface any report (with SMTP) fail.