Consider the following scenario:
You log on to Microsoft Lync 2010, and then you click Phone to view a voice mail history.
You delete the voice mail of a contact that is not in your contact list.
You close the voice mail view.
In this scenario, Lync 2010 still polls for the non-listed contact's voice mail. This issue occurs until you log off from Lync 2010.
To resolve this issue, install the following cumulative update:
2551268 Description of the cumulative update package for Lync 2010: May 2011
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.