Welcome to the Microsoft Unified Communications Managed API 2.0 Software Development Kit (SDK) Release Notes. Refer to this file for information regarding known issues about the application programming interface (API) sets that ship with Office Communications Server 2007 R2.


About This Document

This document contains important information that you should know before you use the Microsoft Unified Communications Managed API (UCMA) 2.0 SDK. For additional information about this SDK and API sets, refer to the documentation included with your installation.

UCMA 2.0 SDK Setup

Setup Does Not Work When User Installs Downloaded MSI �UCMASDKWebDownload.msi� in a Path That Contains Double-Byte Characters


When a user installs the downloaded .msi file UCMASDKWebDownload.msi in a path that contains a double-byte character set (for example, %Systemdrive%\UCMA??\) and then clicks SetupUCMASdk.exe from that path, no Install button appears in the setup wizard to install the SDK.


Use the default installation location or a location without double-byte characters to install the downloaded .msi file.

UCMA 2.0 SDK Installation Fails in Windows Server 2008 R2


UCMA 2.0 SDK installation can fail in Windows Server 2008 R2 when the prerequisite Windows Media Format Runtime cannot be installed.


In Windows Server 2008 R2, the Desktop Experience feature must be installed before Windows Media Format Runtime can be installed.

To install Desktop Experience by using Server Manager
  1. Open Server Manager: Click Start, point to Administrative Tools, and then click Server Manager.

  2. In the Features Summary section, click Add features.

  3. Select the Desktop Experience check box, and then click Next.

  4. Click Install to complete the installation.

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If You Experience Unusually High CPU Usage, and/or an Increase of CPU Usage Over Time, It May Be Related to a Known Issue in the CLR Thread Pool in .NET Framework 3.5 With SP1


If you experience unusually high CPU usage or an increase in usage over time, profile the application to find out where the process time is spent. If significant time is spent in lock contention methods inside the CLR thread pool, you are likely experiencing a known issue in the CLR thread pool in .NET Framework 3.5 with SP1.

An alternative method for finding out whether you are experiencing this issue is to connect the debugger to the process (or load a dump of the process into the debugger) and run the "!threadpool" command (from sos.dll extension dll). If the queue length is very low (0, 1, or 2), but the total number of worker threads is equal or very close to the maximum limit of worker threads, then you are very likely experiencing this issue.


Limit the maximum number of worker threads in the thread pool by calling ThreadPool.SetMaxThreads(). The number used should reflect the application's needs, and can vary from application to application.

Runtime Message "An application has made an attempt to load the C runtime library incorrectly" Occurs When Running a Communications Workflow Application


At run time, the error message "An application has made an attempt to load the C runtime library incorrectly" occurs when executing a Communications Workflow application.


Install the update available at http://code.msdn.microsoft.com/KB960109 to stop the message from occurring, or click OK to ignore the message. The application should work as expected if you click OK to ignore it.

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Microsoft Unified Communications Managed API 2.0 Windows Workflow Activities

Activities May Not Be Listed in Intellisense in Rule Editor for XOML Workflows


When you develop code-separated workflows, newly added activities may not appear in IntelliSense when you write rules in Rule Editor.


Close the Rule Set Editor dialog box or the Rule Condition Editor dialog box, save the Windows Workflow project, and then try to set the rule set or the rule condition again. For more information, see http://support.microsoft.com/kb/927126.

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