Outlook 2003 Client Configuration with Exchange 2010

When you upgrade to Exchange 2010, your clients running Outlook 2007 or later versions will automatically be compatible with the change to RPC Client Access services in Exchange 2010, since they support RPC encryption by default. Outlook 2003 doesn’t use RPC encryption; however, RPC Client Access requires it by default. If you haven’t turned off RPC encryption, your users will need to configure Outlook 2003 for RPC encryption.

Note: When using the Priasoft Profile Update Manager to update Outlook client profiles, Outlook 2003 clients are configured to support RPC encryption to avoid these issues.

Symptoms of this problem include the following error messages:

• Cannot start Microsoft Office Outlook. Unable to open the Office window. The set of folders could not be opened.
• Unable to open your default e-mail folders. The information store could not be opened.
• If your users are using Cached Exchange Mode, Office won’t display an error, but will start in disconnected mode.

To correct this use the following workarounds:

Option 1: Disable the encryption requirement on all CAS servers

To disable the required encryption between Outlook and Exchange, follow these steps:

On the server that is running Exchange 2010, run the following command in the Exchange Management Shell:

Set-RpcClientAccess –Server Exchange_server_name –EncryptionRequired $False

Note The Exchange_server_name placeholder represents the name of an Exchange Server 2010-based server that has the Client Access Server role.

Rerun this command for each Exchange 2010-based server that has the Client Access Server role.

Option 2: Manually update or create your Outlook profile with RPC encryption

1. In Control Panel, open the Mail item.
2. Click Show Profiles.
3. Select your profile, and then click Properties.
4. Click E-mail Accounts.
5. Select View or change existing e-mail accounts, and then click Next.
6. Select the Microsoft Exchange Server account, and then click Change.
7. In the dialog box that contains your mailbox server and user name, click More Settings.
8. In the Microsoft Exchange Server dialog box, click the Security tab.
9. Click to select the Encrypt data between Microsoft Office Outlook and Microsoft Exchange Server check box, and then click OK.
10. Click Next, and then click Finish.
11. Click Close, and then click OK.

Option 3: Deploy a Group Policy setting to update existing Outlook profiles with RPC encryption

From a client perspective, deploying the Outlook-Exchange encryption setting is probably the simplest solution for organizations that have many Outlook clients. This solution involves a single change on a server (domain controller), and your clients are automatically updated after the policy is downloaded to the client.

The default Group Policy template (Outlk11.adm) for Outlook 2003 Service Pack 3 (SP3) does not contain the policy setting that controls the setting for encryption between Outlook and Exchange. Therefore, you must use a custom Group Policy template to update existing Outlook 2003 profiles so that RPC encryption is used in Outlook-Exchange communication.

You can download the required Outlook 2003 policy template here.

For more detailed information on Outlook and RPC encryption see the follow Microsoft page.