I have a couple of users out of about 50 who, when clicking on an email, experience a delay to show the emails contents. He will click on the email in the viewing pane and the egg timer will appear and maybe 20 seconds later the contents will appear. He is one of only 2 or 3 people who experience this issue. Additionally this doesn't happen each time he wants to read an email, only some of the time.
We have changed NIC's, patch cords, switch ports and wall socket (so the building wiring) with no change. I set up a wireshark packet capture and I see lots of packets with the following messages:
DCERPC (TCP Out-of-order) Response: call ID 88675 ctx_id: 0
DCERPC (TCP DUP ACK 40519#1) mpshrsv > 36135 (ACK)SEq=9937 Ack=4537 Win=65087 Len=0
These messages are repeated over and over, mainly between this host and the Exchange server.
I would love to hear if anyone has any ideas what might be causing this