Article ID: 2459953 - View products that this article applies to.
After you upgrade from Microsoft Office Communicator 2007 R2 to Microsoft Lync 2010, Lync 2010 may crash or stop responding.
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756To resolve this issue, follow these steps:
(http://support.microsoft.com/kb/322756/ )How to back up and restore the registry in Windows
This issue occurs because during the installation process, Lync 2010 adds any known contacts to the default Contacts folder in Microsoft Outlook. Be aware that a best practice is to uninstall Communicator 2007 R2, restart the computer, and then install Lync 2010.
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