Try disabling your main internet browsers pop up blocker before getting to the payment page.
The billing address on your credit card and the mailing address on your tax return have to match or you will get an error for paying with a credit card.
If they are not the same then change your mailing address to your billing address. Click on My Info on the left side of the screen. Edit you mailing address and Continue. Go back to the File section to make your payment.
After the payment has been approved, go back to My Info and change the address back to the original.