We have one issue in EXM, that it's not updating "Sent" count, although emails are getting delivered successfully. EXM version is 4.0.0 rev. 161028 and Sitecore version is 8.2. (Also it's not sending email delivery completion notification). I am using Sitecore Email Cloud. Can someone please advice that what could be the possible issue?
Issue is fixed after enabling below configuration files in CM server.
Below link has more detail regarding this fix.