And Hi,

Excellent article on TrustModelData by Terence Luk:

http://terenceluk.blogspot.fi/2013/02/location-of-trustmodeldata-registry-key.html

Location of the “TrustModelData: registry key for the Lync 2013 Client

Those who are familiar with the certificate warning message:
Lync cannot verify that the server is trusted for your sign-in address. Connect anyway?
… that is presented by the Lync 2010 client when signing into a domain that is different than your sign in address:
Sign-in address: tluk@terence.com
Lync Server FQDN: lync2010.terence.local

may have come across the following Microsoft KB that demonstrates a way
to add trusted sign-in addresses via the registry to prevent this
prompt:
http://support.microsoft.com/kb/2531068?wa=wsignin1.0
The KB article states that the following registry locations is where the TrustModelData REG_SZ is supposed to be created:

  • HKEY_CURRENT_USERPoliciesMicrosoftCommunicator
  • HKEY_LOCAL_MACHINEPoliciesMicrosoftCommunicator

This
works great in the Lync 2010 Client but while tackling an issue I had
with the new Lync 2013 Client this week (I will write a separate post
about it), I noticed that the location has changed for the new client
and the new location is the following:

HKEY_LOCAL_MACHINESOFTWAREPoliciesMicrosoftOffice15.0Lync
Name: TrustModelDataType: REG_SZ
 
image
If more than one domain is required for the trusted sign-in address then it can be entered in the following format:
domain.local, domain.com
… where the domains are separated by a comma and a space.