Hi,
In all current Cognos releases (BI and CA) the Microsoft SMTP is not supported (via o365 with TLS).
If you're interested in this functionality, you can vote to the existing feature request. For voting is an Account (IBM ID) necessary:
the link doesn't work directly. only copy and paste in a new tab will works:
h**p://www.ibm.com/developerworks/rfe/execute?use_case=viewRfe&CR_ID=79427
Best Regards