Tried to upgrade from XP HOME to XP PRO.
Message states doesn't support upgrade from XP Home .
The upgrade from Home to Professional is definitely supported. If you
are using a Retail version, either Full or Upgrade, this should work
without a problem, and is the most likely successful of all possible
upgrades, since so little has to be changed.
If it doesn't work, you are probably trying to do this with an OEM
version, which won't do an upgrade from *anything*, and will only do a
clean installation.
Would like to upgrade & retain all data & Programs
Then you need a retail version.
But why do you want to do this? Are you aware that XP Home and
Professional are identical except that Professional includes a few
features (mostly related to security and networking) missing from
Home? Most home users don't need and would never use these extra
features and will see no benefits by upgrading.
For details go to
http://www.winsupersite.com/showcase/windowsxp_home_pro.asp
http://www.microsoft.com/windowsxp/whichxp.asp>
http://www.microsoft.com/windowsxp/home/howtobuy/choosing2.asp
Also note another point, not included in any of the above:
Professional allows ten concurrent network connections, and Home only
five.