Configuring Office Communication Server 2007 R2 integration with Exchange Server 2010 SP1

A new feature in Outlook Web App (OWA) is the possibility to integrate it with Office Communication Server 2007 R2 and to be able to use OWA as a client for OCS with IM, contact list and presence.


To configure the integration you have to do the following steps:

1. Download the Microsoft Office Communications Server 2007 R2 Web Service Provider
2. Run the CWAOWASSPMain.msi file and select a location to install the files

3. From the location selected at the previous point run (in this order):

• Visual C++ Redistributable (vcredist_x64.exe)
• Unified Communications Managed API (ucmaredist.msi)
• OCS Service Provider (cwaowassp.msi) – it has to be run from a command prompt with elevated rights

4. Find out which certificate is used for OWA by running on the CAS server (s) the Get-ExchangeCertificate cmdlet. The one that has W as service is the one that you need.

Thumbprint Services Subject
---------- -------- -------
AB8A56B7676E463A5C823C498FF480C4E83DF0D1 ..U... CN=*.pras.ro, OU=IT, O=IT, L=Bucharest, S=Bucharest, C=RO
0BD7302E7B6015E4F849675B34EB037BBB715FE3 ....S. CN=exch2010
EF5E22DA6B07DD0FE732585E292EAF67BD0AD802 ...... CN=WMSvc-EXCH2010
54E2F64780F295685694FA5CA525D5193FFDAF02 IP.WS. CN=mail.pras.ro, OU=Information Technology, O=PRAS Consulting S...

5. On the CAS server run: Get-OwaVirtualDirectory
fl InstantMessage* to get the current OCS integration settings. You should get a result like:

InstantMessagingCertificateThumbprint :
InstantMessagingServerName :
InstantMessagingEnabled : False
InstantMessagingType : None

6. Run the following cmdlets on the CAS server (ocspoolname is the pool name from your OCS installation, thumbprint is the one obtained at step 5)

• Set-OwaVirtualDirectory “owa (default web site)” -InstantMessagingServerName ocspoolname
• Set-OwaVirtualDirectory “owa (default web site)” -InstantMessagingCertificateThumbprint thumbprint
• Set-OwaVirtualDirectory “owa (default web site)” -InstantMessagingEnabled $True
• Set-OwaVirtualDirectory “owa (default web site)” -InstantMessagingType OCS

7. Reset IIS server by running on command prompt: iisreset /noforce

8. On the OCS server, add Exchange CAS name(s) to the Host Authorization tab.

• While logged in as an OCS administrator, start the OCS Management Console
• Navigate to the OCS 2007 R2 Pool. Right-click the OCS Pool name and select Properties, then select Front End Properties
• Click on the Host Authorization tab, then click the Add button.
• In the Add Authorized host window, select the FQDN radio button and type the name of the CAS
• Select (checkbox) the following options: Treat as Authenticated and Throttle as Server.
• Click OK to save the configuration changes.
• To allow changes to take effect immediately, stop and restart the OCS front-end services; note that doing so will disconnect any active users.

That should do it, when you will open a new OWA client you should be able to see the presence info, your contact list and to be able to IM them