Microsoft recommends that you carry out the following steps before upgrading a system to Windows XP:
- Make sure all hardware in the system appears on the Hardware Compatibility List (HCL).
- Ensure hardware meets the minimum system requirements.
- Use winnt32 /checkupgradeonly to run the Windows Readiness Analyzer and generate a Compatibility Report to make sure that all hardware and software is supported on the system being upgraded.
- Backup all files.
- Scan for viruses and then disable antivirus software as it may interfere with the upgrade process.
- Uncompress any compressed drives. Only compressed drives using NTFS file system compression can be upgraded safely.
- If you are upgrading a Windows NT 4.0 system using spanned or striped sets, you must backup the data, delete the spanned or striped sets in Disk Manager, upgrade to XP, convert the disk to Dynamic (covered later), create spanned or striped volumes, and then restore backed up data.
The following operating systems can be directly upgraded to Windows XP Professional. The setup routine will preserve and migrate all possible software and settings:
- Windows 98
- Windows Millennium Edition
- Windows NT 4.0 with Service Pack 6
- Windows 2000 Professional
Earlier versions of Windows must be upgraded to a supported operating system first before upgrading to Windows XP Professional:
- Windows 95 -> Windows 98
- Windows NT earlier than NT4 SP6 -> Windows NT4 SP6
Next: Performing the Upgrade