i am currently using xp home and i want to upgrade to xp pro.
a little while ago i installed xp pro on vmware to try something out, then i deleted it from vmware.
when i want to upgrade my system will i have to use the product license key, since i already used it before? if i do need to use it will i be able to use the some one again since i am using it on the same system?
will i loose any of my files on my computer? some people are saying that i should backup everything up just in case and some are saying i don't need to.