Microsoft has released a document on Migrating from Windows Small Business Server 2003 to Windows Small Business Server 2011 Essentials and it is now available for download.
This guide explains how to install Windows Small Business Server 2011 Essentials in migration mode on a new server, and then migrate the settings and data from the old server that is running Windows Small Business Server 2003 to the new server that is running Windows SBS 2011 Essentials.
This guide also helps you demote and remove your old server from the network after you finish the migration process.
This Migration Guide includes the following steps:
1. Prepare your Source Server for Windows SBS 2011 Essentials migration. You must ensure that your Source Server and network are ready for migration. This section guides you through backing up the Source Server, evaluating the Source Server system health, installing the most recent service packs and fixes, and verifying the network configuration.
2. Create a migration answer file for Windows SBS 2011 Essentials migration. An answer file is used by Windows SBS 2011 Essentials Setup to automate the installation and run Setup in migration mode. This section introduces you to the migration answer file and guides you through using the Answer File Tool to create the migration answer file.
3. Install Windows SBS 2011 Essentials in migration mode for Windows SBS 2011 Essentials migration. This section explains how to use the migration answer file to install Windows SBS 2011 Essentials on the Destination Server in migration mode.
4. Move settings and data to the Destination Server for Windows SBS 2011 Essentials migration. The Migration Wizard helps you migrate settings and data from the Source Server to Windows SBS 2011 Essentials. This section explains how to use the Migration Wizard and provides information about the settings and data that you can migrate.
5. Demote and remove the Source Server from the new Windows SBS 2011 Essentials network. Prior to removing the Source Server from the network, you must force a group policy update and demote the Source Server.
6. Optional post-migration tasks for Windows SBS 2011 Essentials migration. After you finish migrating all settings and data to Windows SBS 2011 Essentials, you may want to map permitted computers to user accounts and enable folder redirection.
7. Run the Windows SBS 2011 Essentials Best Practices Analyzer. After you finish migrating settings and data to Windows SBS 2011 Essentials, you should download and run the Microsoft® Windows® Small Business Server 2011 Best Practices Analyzer.
Download page: Microsoft.