Since SysAid uses EWS, try going to your mail server URL through *Internet Explorer*, and instead of /owa, type /ews. A login page should be displayed, and once logged in you should see an XML sheet. If this is not what it occurs, it's possible that EWS has been disabled and SysAid email integration will be unable to log in. Please enable EWS in your mail server.
Let me know if this works.