I recently deployed a Microsoft Lync Server 2013 infrastructure for a customer running Microsoft Exchange Server 2007 SP3, and while this version of Exchange Server is supported it should be noted there are a few additional amendments that need to made in order to make UM Auto Attendant key mappings to Lync extensions work correctly. Following the typical UM integration through the use of OCSUMUtil.exe and ExchUMUtil.ps1, all Unified Messaging functionality seemed to be working correctly, including dial by extension. It wasn’t until a key mapping was added to an Auto Attendant to transfer a call to a specific Lync extension, did I see an issue. When calling the attendant and pressing one for example, which was directed to extension 319, the Unified Messaging service would produce the following error and the attendant would tell the caller “The call could not be transferred”.
As you can see, there is not a specific amount of detail to go on and researching this particular Event ID suggested this was an error that could pertain to a number of issues. On researching further however, I noted the following from the TechNet article on integrating Lync Server 2013 with Exchange Unified Messaging:
If you are using a version of Exchange that is earlier than Microsoft Exchange Server 2010 SP1, you must enter the fully qualified domain name (FQDN) of the corresponding Exchange Unified Messaging (UM) SIP dial plan in the Lync Server 2013 dial plan Simple name field. If you are using Microsoft Exchange Server 2010 SP1 or latest service pack, this dial plan name matching is not necessary.
In order to resolve the key mapping issue the following was performed.
1. Connect to the Lync Server 2013 control panel and click Voice Routing and then select the Dial Plans tab.
2. Double click the “Global” dial plan to edit it and in the Simple Name dialog box, remove the word Global and replace it with the name of your Exchange Unified Messaging dial plan followed by your internal Active Directory domain name. For example, if my UM Dial Plan name was “DefaultUM” and my internal domain was “company.local”, I would enter DefaultUM.company.local into the Simple Name field.
3. Click OK and then commit the change, you will then need to wait a few moments for the change to take affect before trying the key mapping again. It should also be noted that in the Global dial plan you will need sufficient normalisation rules for the key mapping to work when transferring to an extension. In my case the dial plan now looked like the following:
That’s it, hopefully your Auto Attendant key mapping issues to Lync extensions will now be resolved.