This article describes how to change the location of the message tracking log files in Microsoft Exchange Server 2003.When message tracking is enabled on a Microsoft Exchange Server 2003 computer, the tracking logs are written to the following default location:
C:\Program Files\Exchsrvr\ServerName.log
In this scenario, C:\Program Files\Exchsrvr represents the folder where Exchange Server 2003 is installed and ServerName is the host name of the Exchange Server computer.

Here is an update from Microsoft for Outlook 2003's junk email filter. This update enhances the junk e-mail filter, helping to provide a higher level of protection against junk e-mail.

Download the update from Microsoft

For more, read the KB Article 

Situation:
When you try to book a resource like a conference room, for example, by using a resource mailbox that has been configured to automatically accept meeting requests, the meeting request is not automatically accepted. Additionally, you cannot book the resource, and you do not receive the following confirmation message:

Use the following procedures, If you want to move log files or database files to another drive:

To move log files

1. Start Exchange System Manager.  
2. Click Administrative Groups.
3. Locate the storage group where you want to change log file paths, right-click the storage group, and then click Properties.  Read more..

When you troubleshoot Simple Mail Transfer Protocol (SMTP) problems, you may want to obtain the Domain Name System (DNS) records for the SMTP domain in question. You can use the Nslookup.exe utility to collect this information.

DNS must be configured properly on the computer running the Nslookup.exe utility. If DNS is not configured, an error message is displayed when the Nslookup.exe utility starts.

1. Start Exchange System Manager.
2. Expand Administrative Groups, expand Your_Administrative_Group, and then expand Servers.
3. Expand Your_Server_Name, and then expand Your_Storage_Group.
4. Right-click the mailbox store object that you want, and then click Properties.
5. Click the Database tab.
6. In the Maintenance interval box, click an appropriate schedule.

The EXIFS (M: drive) feature has been disabled by default. If the feature is still needed, it can be assigned to an available drive letter with a registry setting.

A border server is an Exchange server that communicates with external servers. In a single server organization, your server is by default a border server. In a multi-server configuration, you may have one or more dedicated servers that communicate directly or indirectly with foreign servers and then pass the mail to other internal Exchange servers.

Dynamic DNS (described in RFC 2136) allows servers to dynamically update and create records in DNS. Dynamic DNS is used by the Exchange server to create server records and other entries used by the Exchange Servers for things like message routing. In a simple Exchange organization, DDNS is not strictly necessary, but makes administration much easier.

DSAccess implements a directory access cache that stores recently accessed information for a configurable length of time. This reduces the number of queries made to global catalog servers.