Hi Lin I have CS4 extended which would not load on my HP machine, which has XP sp3, and I had bought it on a CD.I do not have much Adobe software so I removed it all from my computer, after 3 days of trying to load it.CS4 then loaded without any problem!I did not try to get any help from Adobe as I have found that the problems you have with Adobe aply to many other companys,and it is not worth the effort trying.When you have bought these item you are on your own.This also aplys to insurance I bought cover from a Company in the U.S.and they refused to cover the cost of the repair. the cover still had 3 month to go. I will only buy insurance cover from a UK company now and if they wont pay I can take them to court!That is my curent Rant! Kind Regards David Evans