Symptoms
No response from Smartaction when integrate with Exchange Online

Diagnoses
When end users try to action the task via email, they didn't receive any response from SmartAction Listener. This only happen after migration to O365

Resolution
During the session, we notice couple of items:-
1) EWS URL is wrong in Setup Manager. It should be https://outlook.office365.com/EWS/Exchange.asmx instead of https://smtp.office365.com/EWS/Exchange.asmx. This is a standard URL for all O365 Exchange. Moreover, SmartAction wouldn't work with any SMTP servers.
2) After that, we reconfigure the Blackpearl via Setup Manager again and notice the Blackpearl server is complaining about the spam restriction. We turned off the SpamRestriction in K2HostServer.exe.config (refer to "Security Recommendation" section in http://help.k2.com/onlinehelp/K2blackpearl/UserGuide/current/webframe.html#K2_SmartActions_Email_Security.html)