By now, you’ve probably read a number of articles debating the use of instant messaging (IM) in the corporate workplace. IM supporters praise its many business justifications; critics say that IM is a scourge of businesses in general and IT departments in particular. But despite the controversy, IM appears to be here to stay, and IT departments need to take charge of the technology in their organizations by implementing a safe, reliable IM service.

If, after considering the IM question, you decide to deploy IM services using your Exchange 2000 server, you’ll need some pointers on installation and configuration. This article will show you the steps to get instant messaging up and running on Exchange 2K.

Instant messaging articles

A few preliminaries
Before we get started, let’s first take a brief look at how Exchange 2000 IM works. The instant messaging infrastructure that comes with Exchange 2000 depends heavily on these five major components:

  • Instant Messaging Client
  • Rendezvous Protocol (RVP)
  • Internet Information Services (IIS)
  • DNS
  • Active Directory

All of these components must exist within your network environment and function correctly before you use IM.

The Exchange 2000 IM Service uses the same MSN Messenger client software as the .NET Messenger Service. You can get the latest version of the Exchange 2000 IM client update from Microsoft’s Web site.

However, the MSN Messenger client update for Exchange 2000 Instant Messaging Service allows you to simultaneously connect to both your internal Exchange 2000 IM Service and the .NET Messenger Service. This is not necessarily good news for the most of you, since the .NET Messenger Service can introduce external security risks and productivity issues for your employees. If you don’t want your users to access the .NET Messenger Service, you’ll need to set up an IM policy that states that.

Exchange 2000 IM works over the Rendezvous Protocol (RVP), a subset of WebDAV/HTTP 1.1 standards, and uses port 80 to transmit presence information and messages. Actually, Exchange IM runs as part of Inetinfo.exe via the IM virtual directory, hence the importance of IIS.

DNS is the method by which the IM client finds an IM server. You’ll need to add additional records to your DNS server to accommodate this. We’ll walk through that process shortly.

Finally, some of the schema changes applied when you first installed Exchange 2000 in your Active Directory forest included attributes specific to IM, such as which users are allowed to use IM and which IM server will handle the IM logon. Therefore, you must have an AD account before you can use IM. Note that Windows 9x and NT 4.0 clients must also have the Active Directory client installed to use IM.

Setting up the server
In this setup, we will configure only one Exchange IM server. IM uses a URL to determine where it should send the message or status request. If a single Exchange 2000 server is running IM, all traffic goes to that server. If we were setting up more than one IM server in our organization, an IM Router would pass the messages to the appropriate IM Home server.

As always, if this is your production environment, remember to back up your Exchange server before you start.

First, we’ll install the IM service. Note that when you install IM, all the Exchange services, as well as IIS, will be stopped. For an existing Exchange 2000 installation, simply rerun the Exchange 2000 Setup Wizard and select Change next to Microsoft Exchange 2000. Then, choose Install next to Microsoft Exchange Instant Messaging Services, as shown in Figure A.

Figure A
Installing the IM service

For first-time Exchange installations, choose Custom next to Microsoft Exchange 2000 and then select Install for the Microsoft Exchange Instant Messaging Services. For both existing and new Exchange installs, you’ll want to reapply SP1 for Exchange.

After Exchange finishes installing, updating, and starting the services, you can create an Instant Messaging virtual server. This is accomplished using the Exchange System Manager. From System Manager, navigate to the server that will host IM. Under Protocols, you’ll see Instant Messaging (RVP). To create a new RVP virtual server, right-click on Instant Messaging RVP, point to New, and select Instant Messaging Virtual Server, as shown in Figure B.

Figure B
Creating a new IM virtual server

The IM Virtual Server Wizard will now present you with a series of choices. First, choose a display name for your Exchange IM server. This display name will be what you use when selecting your Exchange IM within an MMC snap-in. Next, select which IIS Web site to associate with your IM server. Then, type the DNS name you will use to refer to your IM server when using a URL. This should be a complete DNS name, such as the one shown in Figure C.

Figure C
Selecting a DNS host name

Click Next and select the Allow This Server To Host User Accounts check box to set up this IM server as a home server.

Setting up DNS
Now you can make those necessary DNS entries, as mentioned above. You’ll need to navigate to your DNS server and add a service location (SRV) record for RVP that points to your single IM server.

In DNS Manager, select the zone that corresponds to your DNS domain. Right-click on the zone and select Other New Records. Choose Service Location and then click on Create Record. Type _rvp in the Service field and 80 in the Port Number field, leaving the other fields set to their defaults. Next, enter the fully qualified domain name of the IM Home server in the Host Offering This Service field, as shown in Figure D. If a Host (A) record for the hostname of the IM server doesn’t already exist, you’ll need to add one by right-clicking on the zone name and selecting New Host.

Figure D
Creating the DNS records

Enabling user accounts for IM
By default, user accounts do not have IM access enabled. You can enable IM for one user at a time by going into each user’s Properties sheet in the Active Directory Users And Computers console. (Alternatively, you can enable IM for a group of users by selecting the group and running the Exchange Task Wizard.) In each user and/or group click on the Exchange Features tab (Figure E).

Figure E
Setting up users’ access to IM services

If you followed the instructions above, the Instant Messaging User Address should match the e-mail address. You can check the IM User Address by highlighting Instant Messaging and clicking Properties, as we’ve done in Figure F. This simplifies the process of locating other IM users within an organization.

Figure F
Viewing a user’s IM addresses

Now that your Exchange IM services are configured, you are ready to set up your IM client. The only task here will be to inform your instant messaging clients (employees) of the new IM URL address. Once logged on, they will easily be able to add contacts to their IM client, change presence information, send files and e-mails, and use all the other great features of MSN Messenger (Figure G), and the IT department will have the security and manageability of Exchange 2000 IM as the backbone of these services.

Figure G
IM client connected to Exchange 2000 IM

Users may receive the common error message “Logon to Microsoft Exchange Instant Messaging failed because the service is not responding. The service is not available or you may not be connected to the Internet.” If so, you will probably need to make a change to your users’ Internet Explorer settings. If your Internet Explorer is set up to use a proxy, you will need to include the IM server’s domain name in the proxy exceptions field.

As you can see, setting up an Exchange IM server is a fairly straightforward process. Of course, a more complicated environment with multiple servers will involve a slightly different configuration. But by following these instructions, you’ll have the foundation of a core Exchange 2000 IM server in your organization in very little time.