vista oem won't load

[Roy Rogers]

My e machines EL 1200 came with windows XP loaded and a disk with home premium full version vista. I tried upgrading to vista but no luck.I wasn't provided a registration number, It loads fine but then expires. there are some numbers on the white envelope the disk came in but they don't match the pattern required for verification (key). I tried several times to contact e machines, made by gateway, but have received no reply. any suggestions on how to get the registration numbers?

 

[Gareth]

Is the registration key on the back of the computer or on the side panels? Thats usually where OEMs put them.

 

[Roy Rogers]

found it there, thanks