Large increases in load on the Office 365 authentication system because of recurring authentication requests from Lync 2010

You notice that the Active Directory Federation Services (AD FS) server is experiencing larger than expected loads. These loads are more than 40 percent greater than expected. When you examine the traffic, most of the load is from recurring authentication requests from Microsoft Lync 2010. Lync 2010 is continually requesting Office 365 authentication system tokens. This may be because of failed requests to Exchange Web Services (EWS). Each EWS request that Lync 2010 retries to send requires a new Office 365 authentication system token, and the Office 365 authentication system requests are causing the increase in authentication traffic to the AD FS server.