Hi Everyone,

We are in the progress to migrate to Exchange 2013. UM role is enabled on our servers, services are running, however, there is no Dial Plan set up. All the users are already on Lync 2013 with voice. I have no details to that as it is managed by a 3rd party vendor. There are no UM mailboxes enabled.

In such cases what happens when someone has a missed call in Lync?

As far as I know, missed call notification is set up in the dial plan.
(Set-UMMailboxPolicy -identity MyUMMailboxPolicy -AllowMissedCallNotifications $true)

Will users get the notification since the services are running and no policy has been set up to prevent it or is it disabled by default. Is it maybe a moot point as a dial plan is required to be able to handle such a feature?

Secondly, if it is not set up in Exchange UM, can Lync 2013 somehow still send these notifications?

Thank you for your thoughts,
Best regards,
Szabolcs

Hi Szabolcs,

Its not going to work via UM, unless you have the Exchange UM Integration done. Even though the UM services are running they are not doing much work or consuming resources.

Integration part involves creation and configuration of a Session Initiation Protocol (SIP) URI dial plan in Exchange UM.

When youre integrating Microsoft Lync Server with Exchange Unified Messaging (UM), you have to run the ExchUcUtil.ps1 script in the Shell. The ExchUcUtil.ps1 script does the following:

Creates a UM IP gateway for each Lync Server pool.

Creates a UM hunt group for each UM IP gateway. The pilot identifier of each hunt group specifies the UM SIP URI dial plan used by the Lync Server Front End pool or Standard Edition server thats associated with the UM IP gateway.
 
Grants Lync Server permission to read Active Directory UM container objects such as UM dial plans, auto attendants, UM IP gateways, and UM hunt groups.

Read below for detailed steps:

Deploying Exchange 2013 UM and Lync Server overview

Now for your question of these notifications without using UM and just Lync directly.

Lync will leave a missed call notification in your Inbox if the call is not answered. This is default behaviour for Lync and does not require UM for it to work.

Lync can deposit the MCN in two ways, using the local Outlook profile and MAPI, or using EWS (Exchange Web Services) to contact Exchange directly over HTTPS.

References:

Missed calls without UM

In addition to the infos from Satyajit321. Missed Calls will work without Exchange UM only if the Cleint is running.

Without a running Lync client, no notifikation, because the Lync server could not send the notification to the Exchange UM server.