hello..i really need your help....i have cd of photoshop version 7.0 (i think) and i put it in my pc cd place thing..it works..but it asks for d serial num. after i put d cd on...and there is a s.number on d cd,but, it's blur and one part of them are gone..so..how should i know or istall w/o serial num..?..coz i have d cd..it's an old cd...!...pls...!....another way pls...!....