In a Microsoft Exchange Server 2007 and Microsoft Exchange Server 2003 mixed environment, an Exchange 2007 server is running the Client Access server (CAS) role. When mobile devices connect to the Exchange 2007 server to access mailboxes on an Exchange 2003 back-end server, the mobile devices cannot access their mailboxes. These mobile devices also may be prompted multiple times for a username and password. This occurs even though you enabled Integrated Windows authentication on the Microsoft-Server-ActiveSync (MSAS) virtual directory in the Internet Information Services (IIS) Manager on the Exchange 2003 back-end server. Additionally, the following event is logged on the Exchange 2007 server that is running the CAS role:
Event Type: Warning Event Source: MSExchange ActiveSync Event Category: Configuration Event ID: 1036 Description: The proxy request has failed to authenticate on <Exchange Server 2003>. Please ensure that Integrated authentication is turned on.
This problem occurs because the DS2MB process on the Exchange 2003 back-end server turns Integrated Windows authentication off.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:
Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
Microsoft Exchange Server 2003 Service Pack 2 (SP2) must be installed before you apply this hotfix. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
836993 How to obtain the latest service packs for Exchange Server 2003
You do not have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.
Steps to enable Integrated Windows Authentication after you install hotfix 937031 on the Exchange 2003 back-end server
To work around this problem, turn on Integrated Windows Authentication. To do this, follow these steps:
Start Exchange System Manager.
Expand Administrative Groups, expand Administrative_Group_Name, and then expand Servers.
Expand Your_Server_Name, expand Protocols, and then expand HTTP.
Expand Exchange Virtual Server, right-click Microsoft-Server-ActiveSync, and then click Properties.
Click the Access tab, and then click Authentication.
Click to select the Integrated Windows Authentication check box.
Click OK two times. To verify that this successfully replicated to the metabase on the Exchange server, follow these steps:
Open the Internet Information Services (IIS) Manager under Administrative Tools.
Expand the Computer, expand Web Sites, and then expand Default Web Site.
Right-click Microsoft-Server-ActiveSync, and then click Properties.
Click the Directory Security tab, and then select the Edit button under Authentication and access control.
Verify that the Integrated Windows Authentication check box is selected.
Note If this check box is selected, you have successfully replicated the change that was made in the Exchange System Manager to the metabase on the Exchange server.
Click Cancel two times, and then exit Internet Information Services (IIS) Manager. You can now test synching with your mobile device.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
It may be possible that the underlying problem is due to a misconfiguration of the NTAuthenticationProviders in the IIS metabase. You can configure IIS to support both Kerberos and NTLM protocols by running the following command:
cscript adsutil.vbs set w3svc/ WebSite /root/NTAuthenticationProviders "Negotiate,NTLM"
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
215383 How to configure IIS to support both the Kerberos protocol and the NTLM protocol for network authentication