Select the product you need help with

ErrorServerBusy response code when you synchronize an EWS-based application to a mailbox in an Exchange Server 2010 environment

Article ID: 2800080 - View products that this article applies to.

Symptoms

When you try to synchronize an Exchange Web Service (EWS)-based application to a mailbox in a Microsoft Exchange Server 2010 environment, you receive an ErrorServerBusy response code and an error message that resembles the following:

The server cannot service this request right now. Try again later.

Back to the top | Give Feedback

Cause

This issue occurs because the EWS monitoring detects that the limit for the requests that are from a Client Access server to a Mailbox server was reached. Therefore, the Client Access server returns an ErrorServerBusy response code to all EWS requests to the Mailbox server.

Back to the top | Give Feedback

Resolution

To resolve this issue, install Exchange Server 2010 Service Pack 3 (SP3) on the Exchange Server 2010 servers. For more information about Exchange Server 2010 SP3, click the following article number to view the article in the Microsoft Knowledge Base:

2808208

(http://support.microsoft.com/kb/2808208/ )

Description of Exchange Server 2010 SP3

Back to the top | Give Feedback

Workaround

To work around this issue, make the following changes in the Web.config file on the Client Access server:

Find the following code in the Web.config file:
<add key="MbxServerEnableConcurrencyControl" value="true" />
Change the MbxServerEnableConcurrencyControl value from true to false.

Add the following line of code into the Web.config file:

<add key="MdbFairUnhealthyLatencyThreshold" value="500" />

Note The Web.Config file is located in the following path:

Drive\Program Files\Microsoft\Exchange Server\V14\ClientAccess\exchweb\ews

Back to the top | Give Feedback