I can't get it to register :(

I have followed the instructions to the letter and I still can’t get it to work. I get two screens. First it pops up and says it has validated successfully. Then I click okay. Right after that another window pops up saying invalid registration details. Please register the serial number and name to matcher your order confirmation e-mail. I’ve checked my firewall. I’ve copied the information from the invoice page as well as my email. I’ve checked for white spaces. I’ve done everything I can think of that may be causing this issue. Please assist. I really like this program and would like to support it if possible. Oh, and I’ve uninstalled and reinstalled, still the same thing.