Using New Outlook on Windows for personal email, calendar, and contact management
You need to go to setting then apps and features
click on Outlook then advanced options
Then turn off Background Apps
That will stop it from launching everytime windows starts. at least on WIndows 10.
This doesn't work either. New Outlook continues to start at Win10 bootup.
Correction: After turning off Background Apps above, I restarted Windows rather than just doing a shutdown, and this appears to have prevented Outlook from starting up again. I will wait a few days and power cycles to see if this is confirmed.
Results: Nope, this doesn't prevent new Outlook from auto starting. As stated above my new Outlook doesn't show up in any of the start up locations/folders or msconfig either. It appears to have some built in hooks that may not be configurable. What a pain!!!