Invalid serial number

I got a new computer and uninstalled CorelDraw X6 from my old computer and then installed it on my new computer.  After a few days I started receiving the warning that the serial number was invalid.

I've been using this software since it came out with no problems.  It's only installed on one computer.

I called Corel and it took them 2 days to send me an email saying to use the installer they sent.  I did and I'm getting the error again.

Corel's customer support is a joke.