activation key not valid

I have recently got a new Mac and decided to put parallels back into my machine, so found my original disk, install and then it asked for the registration key. So I put it in, and it tells me it is not valid.
I own an original copy with the key printed on the inside of the package, how can it not be valid.
Anyone know how to get round this as I have version 10 as an upgrade also to install and can't do that until 8 is accepted.....please help

 

To download and install Parallels Desktop 10, please follow this steps.
To activate upgrade version of Parallels Desktop 10 try this steps.
Please feel free to reach us after followed above steps if the issue persists.

 

I only have a problem with the activation key for parallels 8 not being accepted. I can't even install 10 until this has happened

 

Please check your private message we have sent your license key information.