Article ID: 2566829 - View products that this article applies to.
Consider the following scenario:
To resolve this issue, use one of the following methods.
Microsoft Lync 2013The best method to add external contacts in Lync 2013 is to use the Add Contact icon. For more info about how to add contacts through search or the add contact wizard, go to the following Microsoft website:
Add a contact in Lync
Microsoft Lync 2010Use the Microsoft account together with Public Internet Connectivity (PIC) when you add a user to your Lync contact list. To do this, you must make a change in the search field. A Skype for Business Online user who wants to add the Microsoft account that uses a custom domain, such as <username>@live-contoso.com, must add an address that resembles the following to the search field:
This method allows for a quick resolution if Skype for Business Online users are going to add only a few PIC contacts.
Alternative resolution by using DNSThe Skype for Business Online administrator must add the correct Service (SRV) Federation records to the Domain Name System (DNS) host for the Skype for Business Online environment. The domain owner for the external contact’s custom domain must also add an SRV record that resembles the following example:
_sipfederationtls._tcp.live-contoso.comAdministrators can let Skype for Business Online users add contacts without having to use the special format that was discussed in the "Microsoft Lync 2010" section. To do this, administrators must add an SRV Federation record that Skype for Business Online users can access to add contacts to the Windows Live EASI domain.
port = 5061
server hostname = federation.messenger.msn.com
PIC in Skype for Business Online supports connectivity with Microsoft accounts (msn.com, live.com and outlook.com). However, when you add PIC contacts that use a Windows Live EASI domain such as live-contoso.com, Skype for Business Online can't resolve the Instant Messaging (IM) Federation server based on the domain suffix.
If you directly add a PIC contact by using the contact’s EASI ID (for example, you use JoeAndreshak.@live-contoso.com), a specific SRV record is required in the DNS for live-contoso.com. This SRV record is required because the Skype for Business Online server uses the domain suffix in the user's EASI ID to determine how to route messages. In this example, the Skype for Business Online server tries to use the live-contoso.com domain suffix.
For more info about how to troubleshoot Skype for Business Online federated contacts, click the following article number to view the article in the Microsoft Knowledge Base
2392146Note This scenario also applies to contacts that are logging in to Skype by using their Microsoft accounts.
(https://support.microsoft.com/kb/2392146/ )Skype for Business Online users can't communicate with external contacts
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Article ID: 2566829 - Last Review: April 30, 2015 - Revision: 27.0