Unless specified for a particular upgrade path, or for a particular troubleshooting situation, you do not need to uninstall SnapManager before reinstalling it, or upgrading to a newer version.
You can upgrade to SnapManager 6.0 for Microsoft Exchange Server 2003 from the following older versions of SnapManager:
- SnapManager 5.0 for Microsoft Exchange
- SnapManager 4.0 for Microsoft Exchange
- SnapManager 3.2 for Microsoft Exchange