Suppress Outlook 2010/2013 and Lync 2010/2013 autodiscover message

This message appears, when you start Outlook 2010 or Outlook 2013 and you use DNS SRV record to find your autodiscover service:

Lync 2010 has also sometimes the similar message with “Connect” and “Try Another Server” buttons:

 

In Lync 2013 the message “Lync is attempting to connect to:” looks like this

 

This feature can be fixed with the following registry keys

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Communicator]
"TrustModelData"="online.lync.com, outlook.com, lync.glbdns.microsoft.com, mail.yourdomain.com"

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Office\15.0\Lync]
"Trustmodeldata"="mail.yourdomain.com, lyncserver.yourinternaldomain.internal"

[HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\AutoDiscover\RedirectServers]
"mail.yourdomain.com"=hex(0):

[HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\AutoDiscover\RedirectServers]
"mail.yourdomain.com"=hex(0):

where mail.yourdomain.com is the A record where your _autodiscover._tcp.maildomain.com SRV record points to. 14 and 15 are Outlook versions 2010 and 2013. Communicator part of the registry change is for Lync 2010 and 15.0/Lync part is for Lync 2013.