Before starting any changes on the source SBS 2003 server it is _absolutely critical_ to take a full backup (we use ShadowProtect) and a System State backup:
Note the time it took to run the System State backup shown above: 2 min, 3 sec. With a couple of minutes to get the backup configuration steps done this will be one of the best 5 minutes spent in the entire migration process _if things fail catastrophically_ and there is a need to step back.
That check mark should never be checked if a proper full server backup and a System State backup has not been taken.
Microsoft Small Business Specialists
Co-Author: SBS 2008 Blueprint Book