This article describes the update for the Microsoft Unified Communications Client API SDK.
The authentication protocol that is used by Microsoft Office Communications Server 2007 and its clients has been updated to require a signature in all messages. This includes the first message that carries the challenge response.
The version number of the protocol that is advertised in the challenge response has increased to version 4. Challenge responses that use version 4 of the protocol must contain a signature. The signature is a digest of the identifying headers in the message. The signature is calculated by using the session key.
Client applications that are built by using the Unified Communications Client API SDK must use this update to register and to work with Communications Server 2007. Communications Server 2007 requires the first challenge response message to contain a signature.
This update makes the following changes:
- Memory leak issues are fixed.
- A Redist.txt file and the Microsoft Software License Terms are added to the installation directory.
- The .chm file is updated to provide more-comprehensive help.
Some client applications are built by using the Unified Communications Client API SDK. These client applications do not register to a Communications Server 2007-based server. If you do not apply this update to these applications, you may experience the following issues:
- When you try to initiate any API SDK calls by using these applications to send Session Initiation Protocol (SIP) messages, you may receive the following error message:
- The applications run as recipients in a conversation session. When you try to send a new SIP message to these recipients by using other applications that have the update installed, you receive the following error message:
480 Temporarily Unavailable
- Consider the following scenario. Participant A and Participant B are in a conversation session. Participant A tries to use a Multipoint Control Units (MCU) device to invite Participant B. Participant B does not send any messages that use a signature. In this scenario, Communications Server 2007 does not deliver the invitation information to Participant B.
Update download information
The following file is available for download from the Microsoft Download Center:Download the UccApiSdk.msi package now.
For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:
How to obtain Microsoft support files from online services
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There are no prerequisites for installing this update.
You do not have to restart the computer after you apply this update.
Update replacement information
This update replaces the earlier release version of the Unified Communications Client API SDK that was dated October 8, 2007.
For more information about updates that are related to Communications Server 2007, click the following article numbers to view the articles in the Microsoft Knowledge Base:
Description of the Communications Server 2007 update package: March 2008
Description of the update for the Conferencing Add-in for Outlook: April 11, 2008
Description of the Windows-based Live Meeting 2007 client update package: April 11, 2008
Description of the update for Communicator 2007: April 2, 2008
These updates do not require an API change.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
Description of the standard terminology that is used to describe Microsoft software updates