Effects of Changing a User's SIP Address in Lync Server 2013

A question I get a lot when talking with administrators about Lync is how to handle name changes and what effect changing a user's SIP address has on other users.  In the example below we will look at the effects of changing a user's SIP address and what other user's will need to be aware of.  In the screenshot below, William has Judith as a contact on his contact list.  Judith's last name is changing and so will her SIP address:

After updating the user's display name and changing their SIP address, the user will be signed out of the Lync client:

If we take a look at what actually happened in the database, before making any changes, you can see that each user is assigned a unique ResourceId:

These IDs are what are used by the database to keep track of your contact list.  This means that since your contacts aren't stored with the SIP address being the identifying field, when a user on your contact list has their SIP address changed, you don't need to remove and re-add them to your contact list again.  The only exception to this is federated contacts.  Those contacts would need to be removed and re-added since they aren't part of our Lync environment:

After changing Judith's SIP address, you can see that the ResourceId stayed the same:

Once Judith changes her sign in address in the Lync client, she will be able to sign in successfully and you can see that her updated display name is shown.  Also any contacts that she had on her contact list would still be there:

However, for William Cooper, you can see that his client didn't pick up the changes:

This is because these users will need to sign out and back in before their client will pick up the changes.  After signing out and back in, you can see below that William's client now displays the correct contact:

Joining a meeting that Judith scheduled before her SIP address was updated will produce the following error:

This is because the join URL is referencing her old SIP address:


The meeting information that is stored in the database is valid, but since the join URL is incorrect, Lync is unable to find the correct meeting.  After changing Judith's SIP address her join URL changes to:


This means that any scheduled meetings would need to be updated so that users are able to join without issue.


Searching the address book for Judith may produce inconsistent results:

Since the Address Book service hasn't run yet to update the address book, the Lync client may be pulling some stale information.  In the screenshot above, the old SIP address was still be used so a 404 was being returned to the client.  After updating the address book, searching for Judith produced the expected results:

The Lync client handles SIP address changes fairly well.  Just remember to have users update their meetings and let any federated contacts know that their SIP address has changed.