I'll share the reason why you're unable to register your QuickBooks, @DLWEATHERVANES. 

QuickBooks Pro 2008 is a discontinued version. With the QuickBooks Desktop Service Discontinuation Policy, older versions will no longer receive product updates and cannot access online services. Thus, you received the error when registering.

To re-register the program you'll need a validation code. . I suggest reaching out to our customer care support again so they can generate the code. Then, please ensure you have your license and product numbers handy. It's from that information the code will be generated. Here's how you can get in touch with them:
 
If you cannot access your QuickBooks and the Contact Us button is unavailable from the Help panel, you'll want to consider reaching out to us outside of it. To proceed, visit this site: What can we help you with?

Please know that our support hours are from 6 A.M. to 6 P.M., from Monday through Friday, for the Pro, Premier, and Plus versions. For Enterprise, we're available at any time, on any day.

For other ways of connecting with us, refer to this article: Contact QuickBooks Desktop support. This includes the contact number where you can call us. Just scroll down and go to the Need help getting in touch?

You can also check this article for future reference: Fix license, validation, and registration errors in QuickBooks Desktop.

Don't hesitate to comment below if you have other queries, @DLWEATHERVANES. I'm here to help you. Have a nice day.