You install Microsoft Lync 2010 and Microsoft Outlook 2010 on your computer.
You configure multiple Microsoft Exchange accounts or additional Exchange mailboxes in an Outlook profile.
You configure Lync 2010 to match the default Exchange account.
Exchange Web Service (EWS) is not deployed, or does not work. Therefore, Lync 2010 uses Messaging Application Programming Interface (MAPI) to write the conversation history to the Exchange store. Note To check whether EWS is working, hold the Ctrl key and right-click the Lync 2010 icon in the notification area. Then, click Configuration Information, and check the EWS Information row.
You start some conversations by using Lync 2010.
You check the Conversation History folder in Outlook 2010.
In this scenario, the instant message (IM) history is randomly stored in one of the nondefault account mailboxes.
To resolve this issue, install the following cumulative update:
2701664 Description of the update for Lync 2010: June 2012
For more information about how to use multiple Exchange accounts, visit the following Microsoft website: