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You cannot sign in to Communicator or Lync in Office 365 Dedicated


You cannot sign in to Microsoft Office Communicator or Microsoft Lync in Microsoft Office 365 Dedicated, and you may receive the following error messages:

Microsoft Office Communicator error message:

Cannot sign in to Communicator because the sign-in address was not found. Please verify the sign-in address and try again. If the problem persists, contact your system administrator.

Microsoft Lync error message:

Cannot sign in to Lync because the sign-in address was not found. Please verify the sign-in address and try again. If the problem persists, contact your system administrator.

Note Although this article may be relevant to several deployment scenarios for Microsoft Office Communicator or Lync, this article is focused on this issue in the deployment of Office 365 Dedicated.


This problem may be caused by the following:

  • The user is not entitled for Lync Online Dedicated.
  • The user is not using the correct sign-in address.


Microsoft Managed Services Service Provisioning Provider (MMSSPP) provisions managed-account objects for Lync Online Dedicated. Customers use an entitlement attribute (for example, extensionattribute5) in their Active Directory Domain Services to signal MMSSPP to provision that object for Lync Online Dedicated. The extensionAttribute is specific to each customer.

Important If you are unsure which attribute that your company uses for Lync Online Dedicated entitlement, contact your Subject Matter Expert (SME) or your Microsoft Service Delivery Manager (SDM) for clarification.

The first step in troubleshooting an authentication issue is to determine whether the user is entitled for the service. If the user is not entitled for Lync Online Dedicated, continue to troubleshoot by using the following guidelines. 

address

Verify that the user is using the correct sign-in address and associated domain credentials when the user signs in to Lync Online Dedicated. Typically, the user's sign-in address is the same as the user's email address. However, there are exceptions, and these exceptions are explained in the following: 

  1. The user's email address suffix differs from the supported Session Initiation Protocol (SIP) domain.

    Example 1
    Supported SIP Domain =
    User's email address =
    Lync Online Dedicated sign-in address =

  2. The user does not have a unique mail prefix.

    Example 2
    Supported SIP Domain =
    UserA's email address =
    UserB's email address =
    UserA's Lync Online Dedicated sign-in address =
    UserB's Lync Online Dedicated sign-in address =

    In this situation, the first user to be provisioned for Lync Online Dedicated in the supported SIP domain receives the standard sign-in address. All later users who are provisioned and who have the same email prefix receive incremental sign-in addresses. For example, see UserB's sign-in address ( in Example 2.


Article ID: 2000653 - Last Review: 04/10/2013 08:47:00 - Revision: 16.0

Microsoft Business Productivity Online Dedicated, Microsoft Office Communications Online Dedicated, Microsoft Business Productivity Online Suite Federal

  • KB2000653