Users in my org have a problem from time to time where messages go into sent folder but are not actually received by users sent to and when I check mail flow there is no trace of those mails being sent anywhere, they do not even appear in OWA sent folder.
Recently I applied KB to fix my URI to be the same as external to fix problems with non wild certificate. It worked great and apart from this I don't seem to have any problems. I tried checking both internal and external ip's for autodiscover and URL and they both return proper ip addresses. Did anyone seen a similar problem, or has any idea of what I could do to fix it?