Moving from a Linux Mail Server and peer-to-peer network to Exchange Server 2007 (Part 4)

If you missed the previous parts in this article series please read:




Configuring OWA


Linux users might be using Web Access to access their messages and they don’t have the domain information to add during the webmail access process. To avoid questions in the new OWA, let’s change the default behavior and configure it to accept only user name and password just like they have been using in the Linux box. To configure OWA to accept only user name and password follow these steps:



  1. Open the Exchange Management Console.
  2. Expand Server Configuration.
  3. In the Work Panel, click on the Exchange Server.
  4. In the Result Panel, click on Outlook Web Access tab.
  5. Right-click on OWA (Default Web Site) and then click on Properties.
  6. Click on the Authentication tab.
  7. Check Use forms-based authentication and click on user name only and choose the current Active Directory domain, as shown in Figure 01.


Figure 01: Configuring OWA authentication to user name only



  1. Click on OK in the new window.
  2. Restart IIS to apply the new settings. Click on the Start button, Run and type in iisreset /noforce.


Now, the new users will be able to use only user name and password to access their mailbox through OWA, as shown in Figure 02.


Figure 02: New users using only the user name and password to log on to OWA


Most of the webmail deployments using Linux don’t have any SSL, in this case we will configure a script that redirects the connection to the https URL used by Exchange Server 2007. It’s important because we will change the current Linux host DNS record to the Exchange 2007’s IP address. In this scenario all users will access the new Exchange 2007 OWA instead of the old environment after the switch process.


To create a direct script and apply it in the new environment follow these steps:



  1. Create a default.htm file and copy and paste the following content:
    <script language=”javascript”>
    <! —
     // –>
  2. Save the file in the home folder of the Default web site, c:\inetpub\wwwroot.
  3. Open Internet Information Services Manager.
  4. Expand Web, right click Default Web Site and click on Properties.
  5. Click on the Directory Security tab.
  6. In Secure Communications, click Edit.
  7. Uncheck Require secure channel (SSL).


Starting to use Exchange Server 2007


It’s time to switch from Linux to Exchange Server 2007. Here are some points that must be validated:



  • Validate if the Exchange Server 2007 users’ SMTP Address matches with the SMTP address for the Linux users.
  • If you use the Linux alias file feature, make sure that all entries are in the new environment, in some cases we have to create Groups, add extra e-mail addresses for some users, etc.
  • Validate if a user in Exchange Server 2007 can send external messages. You might have to check the firewall settings.
  • Create a list of all users that work only through Webmail. This list will have priority in the migration to Outlook 2007.
  • Warn users that OWA content will be empty. We need to migrate the data locally to the Exchange database first.


Okay, we have done all prerequisites and all tests are fine, so we can start the switch process:



  1. Schedule a weekend and send a message informing that the message system will be offline for some hours and the new system will be up.
  2. Log on to the Domain Controller.
  3. Open DNS Management.
  4. Find the zone where the current entry of the Linux Server is and all users are using to resolve to the Linux Server, in our case this is
  5. Change the IP Address of the Linux server to the Exchange Server box.
  6. Change the firewall rule that redirects external SMTP traffic to the Exchange Internal IP Address.
  7. Change the firewall rule to allow the Exchange Server 2007 to send external messages (allow 25 SMTP out).
  8. Log on to a workstation and run ipconfig /flushdns to clean up the local cache and try to ping the server name used by Linux in the POP/SMTP setting. The resolution must point to the Exchange Server.


So… how can we test the new environment? Let’s use the new features. Let’s log on to OWA and send a message from Administrator to user Anderson.Patricio.


The user Anderson.Patricio should receive the new messages and all old messages will stay in the same place (locally in the Inbox Folder), as shown in Figure 03.


Figure 03: The new message received in the new environment


By default Outlook Express will configure the Account and all messages will stay on locally; there is no copy of received messages in the mailbox server. This behavior is controlled through the option “leave a copy of messages on server”, as shown in Figure 04.


Figure 04: Maintaining a copy of all received message in the Server


Using this option the same new content will be received in Outlook Express and OWA as well.


Migration Process – Current Status (Update #03)


So, we should now have all workstations accessing Exchange Server 2007 by legacy protocols (POP, SMTP and OWA). We have also changed the Internet message flow to the new server. Our current environment can be seen in Figure 05.


Figure 05: The new environment


The Linux Box server is no longer in use, but if we need some information we can access it through Webmail and POP3 using the Linux server IP address.


Installing Outlook 2007 on workstations


Now we will really move the data from the clients to an Exchange database. In order to configure all clients to use all Exchange Server 2007 features we will install Outlook 2007.


This process is straightforward. After successful installation, we will upgrade the current Outlook Express settings to Outlook and after that we will be able to transfer local messages to the Exchange Server by just moving the messages.



  1. Click on Outlook.
  2. In the Outlook 2007 Startup screen click Next.
  3. E-mail Upgrade Options. Select upgrade option and then click Next.


Figure 06: Upgrading from Outlook Express to Outlook 2007



  1. Most of the information will be filled in already, just click Next to finish this process.
  2. The first time that Outlook runs it will display a dialog box about the import process, click Yes.
  3. Close Outlook.


Now it’s time to remove the POP3/SMTP account settings and define the MAPI profile using Autodiscover.



  1. Click on Start, Settings and Control Panel.
  2. Double click the Mail icon.
  3. Click the E-mail Accounts button.
  4. Click the E-mail tab and click New.
  5. Add an Exchange Mailbox; the profile will be created automatically based on the current user information in the Active Directory, as shown in Figure 07.


Figure 07: Adding the Exchange Server account



  1. Let’s remove the old imported Account. Select the legacy account (the new one is called Microsoft Exchange) and then click Remove. Click Yes to confirm.


  2. Click Data Files and see all the Personal Folder and Mailbox information that you worked on, as shown in Figure 08.


Figure 08: The available Data Files



  1. Open Outlook again see two main items: Mailbox, where all information is in the Exchange Server and Personal Folder, where we have all messages that we were working with in the legacy system. Move the important messages to Exchange and they will be available in OWA as well.


Figure 09: The old content in the PST file and the server content


Final Steps …


Okay, in this article series was demonstrated how to move from a Linux mail server to Exchange Server 2007 using the resources found in Exchange Server 2007 and Active Directory. We moved all network services, workstations and we were able to move them gradually to the new environment.


Have we finished the migration process? Actually no, we still have to check some points:



  • After we upgrade all workstations to Outlook 2007 and configure them to use MAPI instead of POP3 and SMTP, we will be able to remove the Receive Connector for Internal users.
  • We will also be able to disable the POP3 Service.
  • Configure the Firewall to publish the other Exchange 2007 features (RPC over HTTP, ActiveSync, etc.


Finally, we can say that we have finished the Exchange Server 2007 deployment, but your work is not done. You have a lot of cool features to explore like high availability, unified messaging, anti-spam protection, etc.




In this article we switched between messaging environments and we also saw how to upgrade from Outlook Express to Outlook 2007 on the client side. With this process done we were able to move local content to the Exchange Server database through Outlook.


If you missed the previous parts in this article series please read:



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