Hi,

We have both Exchange 2010 and Exchange 2013 running in co-existence.

Exchange 2010, version 14.3 (build 123.4)
Exchange 2013, version 15.0 (build 913.22)

We finished migrating all users to Exchange 2013 some while back. All PF's are migrated too. Nothing is left running on Exchange 2010 and we were all ready to decommission this server.

Then some users started calling saying when they draft an email and save it without sending, they notice the draft will show a sent time in Outlook under the 'Sent' column. I can easily replicate this behavior. 

So, I went to the Exchange 2010 server, created a new user and mailbox, logged into a PC and started Outlook. I created a few draft emails and under the 'Sent' column they show as "none". I then migrate the mailbox to Exchange 2013 and repeated the steps. I immediately get a sent time appear when closing and saving the draft item. The messages created whilst on Exchange 2010 remain untouched in my drafts with a sent time as "none". What is causing this?

When I migrate the mailbox back to Exch 2010 the issue goes away - new drafts appear with a sent time of "none", as expected.

What is causing this problem with Exchange 2013?

I am using Outlook 2010 14.0.7147.5001 with all non-MS add-ins removed. The issue on Exch 2013 happens when using OWA as well, so the type of client appears irrelevant to this issue.

Many thanks.

Hi,

Please install the latest CU of Exchange 2013 to check this issue. The latest CU include all fix in previous version.

https://support.microsoft.com/en-us/kb/3030080

Best Regards.

Really? Just update and hope that fixes it? Your link is broken by the way.

Is there a link you can refer me to which fixes the specific issue I have described?