Exchange 2010 Outlook Anywhere not working and getting HTTP 500 response error


Here is some notes from a recent issue error that I encountered this week with an Exchange 2010 server configured for Outlook Anywhere. For some reason Outlook Anywhere stopped working and the Outlook Anywhere (RPC over HTTP) clients were no longer able to connect.

After checking all the basics in Exchange, like:

  • Confirming the OA settings
  • Certificates (not expired and common name)
  • Firewall rules
  • Autodiscover etc.

Testing Http Authentication Methods for URL

The HTTP authentication test failed.

Additional Details

An HTTP 500 response was returned from Unknown

For Outlook Anywhere confirm the following:

  • That your domain “” is the common name in the certificate and that the output is correct in the EXPR provider
  • That redirection is not configured on the IIS virtual directory
  • Check the SSL settings of /RPC virtual directory, it should be: Require SSL (Checked), Require 128-bit SSL (Unchecked), Client certificates: Ignore
    If the above does not help, you may have to reinstall the RPC Proxy component, I found that reinstalling the RPC Proxy component solved my problem and according to several searches on Google Bing, it seems several others have experienced similar problems with OA and Exchange 2007 and the solution was the same.

The process of reinstalling RPC Proxy is:

  1. Disable Outlook Anywhere using EMC or EMS
  2. Remove RPC proxy component using the command: servermanagercmd -r rpc-over-http-proxy
  3. Reboot the server
  4. Install RPC proxy component using the command: servermanagercmd -i rpc-over-http-proxy
  5. Enable Outlook Anywhere
  6. Restart Microsoft Active Directory Topology service
  7. Check if the issue still exists
    The reinstall of the RPC Proxy component solved the problem for me.

About Author

Peter is an Exchange specialist with over 15+ years of experience with Exchange Server and certified Microsoft Certified Master (MCM) and Microsoft Certified Solutions Master (MCSM) on Exchange Server. He has been awarded the Microsoft MVP award, every year since 2007. He is active in the Microsoft community and User Group Leader for CoLabora (a danish UC & Cloud User Group). He works as an Cloud & Infrastructure Architect and Consulent, with primary focus on Exchange, Office 365, Azure and Skype for Business.


  1. I had the same error and i fixed by selecting either NTLM or Basic authentication in the Outlook anywhere settings on the Exchange 2010 server.
    It seems after SP1 the options for “Negotiate Ex authentication” no longer works.
    Please note: when you change settings you need to wait for a MSExchange RPC Over HTTP Autoconfig event to showup in the event log.

  2. Thank you Peter for posting this. We had this issue occur with our MS Exchange 2010 environment and your instructions worked great. The one place I deviated was step 6 where I just rebooted the server. As soon as the server came back online all was well! Thanks again.

  3. I had the same issue, right click on /rpc and browse and I got the 500 error. In the end I just rebooted, and everything came back, but it's a worry, because I can't see why it stopped in the first place…

  4. Had the same error, restarted IIS (IIS Manager – right click on the server name – stop – wait – right click again – start) – and it’s working again.

  5. It’s appropriate time to make some plans for the future and it’s time
    to be happy. I’ve read this post and if I could I want to suggest you some interesting things or advice. Perhaps you can write next articles referring to this article. I desire to read more things about it!

  6. I cannot connect to an exchange server 2013 with Outlook Anywhere.

    From a windows 7 (with outlook 2010) that belongs to a workgroup, I have no problem.

    The problem resides from a xp professional (also with outlook 2010). The computer belongs to sbs 2008 domain. We pretend to use the remote exchange rather the local one.

    Sorry for my bad English

    Thanks in advance

    The certificate used is the same.

  7. Pham Trung Duc on

    Hi Peter,
    i have followed your instruction but after that all:
    -Disable outlook anywhere via EMC
    -Remove RPC proxy component via PowerShell
    -Command: servermanagercmd -r rpc-over-http-proxy
    -Reboot the server
    -Install RPC proxy component via PowerShell
    -Command: servermanagercmd -i rpc-over-http-proxy
    -Enable outlook anywhere
    -Restart Microsoft active directory Topology service

    I’m still unable to connect Outlook Anywhere to my CAS Server. When i use to test RPC-over-HTTP, this error still appear
    Testing HTTP Authentication Methods for URL
    The HTTP authentication test failed.
    Additional Details
    An HTTP 500 response was returned from Unknown…….

    So could you help me in more detail solution how to fix this prolem ?
    My server is Exchange 2010 SP3 on Windows Server 2008 R2 SP1 Enterprise.
    Thansk for your support !

      • Pham Trung Duc on

        Your solution is great, i have followed it but just one more trick that:
        We have to remove the Old web.config of the RPC virtual directory (C:\Windows\System32\RpcProxy) after we Remove RPC proxy component via PowerShell.
        Maybe the uninstalling process doesn’t entirely remove the RPC Virtual directory folder so after we reboot the server and reinstall the RPC component, it still read the old web.config.
        Some information that i contribute for you.
        Thanks Peter :D:D:D

  8. We performed an “IISReset” on an Exchange 2007 server running on SBS 2008. After performing the IISReset we had this issue. The issue resolved itself after approximately 20 minutes.

    Before troubleshooting this issue, I recommend waiting half an hour to see if it will self correct like it did in our case!

Copyright 2005-2015 - Peter Schmidt.