authentic cd-key being rejected

I'm fixing a dell inspiron 2200 that isn't reconizing the cd-rom. After hours of searching and trying out different drivers unsuccessfully I devided to do a repair install, but dell didn't include a windows xp cd, so I used the one that came with my laptop and when it came to the point to enter the cd key, I flip the laptop over and entered the key from the microsoft sticker but he problem is that it won't accept the cd-key. So now I'm backing up the drive and I'm going to try to use Dell's replacement for the cd which is a separate partition with the image of windows xp which completely destroys everything in the destination partition.

So what should I do about this cd-key? Do I call microsoft or Dell about it? Should I mention that I used the cd of a different machine to do the repair install?

It probably isnt the right type of disc. I would call Dell to get the correct restore CD. They may not just send you the disc though. Many times they require you to buy a complete new CD Key and media kit. Wouldn't hurt to call though.

yeah, you have to use a dell xp cd.

Why would it matter? I don't think they would care. Just reinstall from the backup partition and be done with it. am i missing something?

A repair install doesn't delete anything that is currently installed on the computer, so every application the owner has installed and every setting they changed are preserved, when you use Dell's cd or image from the hdd thing I explained above, the entive partition is erased, and that is a lot of work to get the pc looking like it did before I got my hands on it. As far as I know dell doesn't ship oem windows cds with their computer anymore only the image of the drive on a cd, which is stupid because the user isn't able to do many of the things that a oem windows cd does. Also the cd I'm using is a oem windows xp Home edition sp2 which is the same that was installed on the computer and the sticker with the key says the same.

Well you could try one of those XP key changers if you can get into it or mod the registry key to what you need-maybe could ID to your copy. Not sure about this but dell used to throw a hidden partition on their systems with a buncha crap in it so you may need to bring up the RC and nuke that out prior to trying to slip in a new ID. Also you could do some research and burn a new ISO using yours with a changed PID to the dell distro, but Im not sugesting any of this to circumvent EULA, of course.

Large PC Manufacturers known as Original Equipment Manufacturers (OEMs) have the ability to pre-activate Microsoft® Windows XP software installed on new PCs. As a result, end users are typically not required to activate the software during the set up process by typing in the product key found on the Certificate of Authenticity attached to the PC (COA Key).

Best thing to do would be to slipstream another XP disk for this machine then you can activate it using the options available at the following URL :-
http://unattended.msfn.org/unattended.xp/view/web/29/SESSID=7527742620cf1b00c9ea226c6d1311c6/#backup

Some(and I'm not exactly sure who, although Packard bell and HP used to), never give you a CD, they bury a repair or reinstall setting somewhere on the original HD, and just put a label on the case with the COA(as UM mentioned). I have seen a number of occasions where using a substitute(although legit) copy to install doesn't work on OEM setups with their own key.