Paypal has a service to let non-paypal users to pay using their credit
card. However, if you have a Paypal account and you choose to pay with
your credit card, Paypal does not like it. Here is the message from them
records indicate that this email address is already registered to an
existing Paypal account. To complete this transaction, please enter a
different email address.
To log in to your existing PayPal account, please click the Login button below
First, they made it easy for non-paypal users to transact. Then they
make it hard for existing Paypal users to pay from anything other than
a Paypal account.
It’s an annoyance and hopefully Paypal is working on fixing it. Very simply, Paypal can provide three options
1. I have a PayPal account and I want to pay using PayPal
2. I have a PayPal account and I want to pay using a credit card
3. I don’t have a PayPal account and I want to pay using a credit card
That should take care of it, I guess.