Microsoft Office Communicator 2007 R2 Hotfix KB 2501722
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This cumulative update fixes the following issues:
2489816 (https://support.microsoft.com/kb/2489816/ ) A user is displayed as another user in Office Communicator 2007 R2
2489823 (https://support.microsoft.com/kb/2489823/ ) You hear a loud noise when you call a European PSTN number by using Office Communicator 2007 R2
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