This topic is among a series of steps to help you troubleshoot an unsuccessful RPC over HTTP connection. This article explains how to verify that the RPC Proxy Server Extension is loading properly.

If Outlook clients experience connection problems after you configure all the required settings for RPC over HTTP on the server side, it may be because the RPC Proxy Server Extension is not loading correctly. When clients experience this kind of connection problem in Outlook, they receive an error message that is similar to the following:

To verify that the RPC Proxy Server Extension is Loading Properly

  1. On the Exchange Server, click Start, point to Administrative Tools, and then click Internet Information Services (IIS) Manager on your RPC proxy server.
  2. Under the icon for your RPC proxy server, click Web Service Extensions.
  3. In the right pane, click RPC Proxy Server Extension, and then click Properties.
  4. Confirm that the path of the Rpcproxy.dll file is correct. The correct location is the following:


    For example, the correct location could be the following:


    Examine the path entry carefully because it could be incorrectly set to the following:


    For example, the current location could be set to the following:


    This incorrect path can appear to be correct at a quick glance.

    Additionally, if you experience this issue, the following 404 error is logged in the IIS log on your RPC proxy server:

    2004-01-01 13:13:31 RPC_IN_DATA /rpc/rpcproxy.dll 443 domain\username MSRPC 404 2 1260

Post By Gishore J Kallarackal (2,121 Posts)

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