For Windows NT 4.0 or Windows 2000 Systems:
You can ascent to Windows XP Professional only.
For Windows 98, 98SE, as well as Windows Me Systems:
You can ascent to possibly Windows XP Home Edition or Windows XP Professional.
For Windows 95 Systems:
There is no ascent path. You’ll need to buy the full chronicle of Windows XP as well as perform the purify install.
Article Source: レジストリクリーナー