Topic Last Modified: 2008-04-15

This topic provides information about why public folder free/busy information might not replicate between Microsoft Exchange Server 2003 and Exchange Server 2007. Exchange 2007 users are unable to see the free/busy information for users whose mailboxes reside on the Exchange 2003 server. The free/busy information displays as hash marks for these users in the Outlook Scheduling Assistant page.

Additionally, there could be several 4003 events on the Client Access server. A 4003 event indicates a failure to look up free/busy information for legacy mailboxes. Typically, this information comes from public folders. The following is an example of a 4003 event.

Event ID : 4003

Raw Event ID : 4003

Category : Availability Service

Source : MSExchange Availability

Type : Error

Message : Process 4664[w3wp.exe:/LM/W3SVC/1/ROOT/EWS-1-128114978363374212]: Microsoft.Exchange.InfoWorker.Common.Availability.PublicFolderRequest failed. The exception returned is Microsoft.Exchange.InfoWorker.Common.Availability.PublicFolderRequestProcessingException


The two causes of the problem are as follows:

  1. By default, the option "Require secure channel (SSL)" is selected on the certification authority (CA) server public folder virtual directory. This issue can occur if the common name on the certificate doesn't match the fully qualified domain name (FQDN) of the URL that is stored on the InternalURL attribute of Exchange Web Service.

  2. Forms-based authentication is enabled on Exchange Server 2003. For more information about forms-based authentication, see How to Configure Forms-Based Authentication for Outlook Web Access.


To resolve the problem, use one or more of the following resolutions, as applicable to the situation in your organization.


To modify the InternalURL attribute
  1. On the Client Access server, open Internet Information Services (IIS) Manager.

  2. Under Default Web Site, go to the Public virtual directory.

  3. Right-click Public, and then click the Properties page.

  4. On the Directory Security tab, click View Certificate, and note the "Issued to" name, for example,

  5. Start Exchange Management Shell.

  6. Modify the InternalURL attribute by typing the following cmdlet and then pressing Enter: Set-WebServicesVirtualDirectory -Identity "CAS_Server_Name\EWS (Default Web Site)" -InternalURL

  7. Restart IIS Admin Service.

To disable forms-based authentication
  1. Open Exchange System Manager.

  2. In the console tree, expand Servers, expand the server for which you want to disable forms-based authentication, and then expand Protocols.

  3. Expand HTTP, right-click Exchange Virtual Server, and then click Properties.

  4. In the Exchange Virtual Server Properties dialog box, on the Settings tab, in the Outlook Web Access pane, clear Enable Forms Based Authentication.

  5. Click Apply, and then click OK.

  6. Restart IIS Admin Service.