Internal users sent items but the recipients never received them. They are all internal messages. At least 4-5 users reported. In all cases senders SENT items but that is it.
However, the delivery report all show successful delivery to the recipient mailboxes. So I ran the tracker in Exchange too and it said delivered but it isn’t in their outlook- already searched that with great detail.
The only thing happened Mid-day Thursday we did have the MPLS go down due to a fiber cut in the area. The impact of that is the Mail server was inaccessible during that time, although that still shouldn’t affect mail.
How to tell what happened to the messages? Please advice.