Consider the following scenario:
A user (user A) signs in to a Microsoft Lync 2010 client in a virtual environment that is running Citrix XenApp 6.5. Then, the user starts a peer-to-peer instant message (IM) conversation with another Lync 2010 user (user B).
One of the users, such as user A, invites a new user into the conversation.
In this scenario, the Lync 2010 client of user A crashes.
Additionally, when one of the users, such as user B, starts a new conversation, his Lync 2010 client crashes.
To resolve this issue, install the following update:
3006209 November 2014 update for Lync 2010 (KB3006209)
This issue occurs because of an issue in Lync 2010 Software Development Kit (SDK).
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