This update is no longer available. To fix the issues that are described in this article, install the latest Microsoft Exchange Server update from the following Microsoft Docs article:
Microsoft provides download files only for N-2 versions for an Exchange Server cumulative update (CU), where "N" is the latest CU. The latest CU can be used to recover servers that are running Exchange Server. This includes servers that have a previous CU installed.
Consider the following scenario:
You configure a server that is running Microsoft Exchange Server 2010 Service Pack 2 (SP2) as a Client Access server (CAS).
The server that is running Exchange Server 2010 SP2 is used as a proxy to a server that is running Microsoft Exchange Server 2007.
You install Microsoft Exchange Server 2010 SP2 Update Rollup 1 (RU1) on the proxy server.
In this scenario, the proxy connection fails from the server that is running Exchange Server 2010 SP2 RU1 server to the server that is running Exchange Server 2007. And, you receive an error message that resembles the following:
Invalid user context cookie found in proxy response
Additionally, an event that resembles the following is logged in Event Viewer:
This issue occurs because of change to the user context cookie in Exchange Server 2010 SP2 RU1.
To work around this issue, use redirection instead of using a proxy.
For more information about Update Rollup 7 for Exchange Server 2007 SP3, visit the following TechNet website: