Testing opencart 1.5 version with checkout. If I checkout as a Guest, it works all the way thru to adding taxes, option for payment, and final success.

If I try to use the customer accounts that are setup, one of which I have as the same email as I used for guest, it won't let me past step 2 I think it is, the one where name and address is filled it. It gives an syntax error undefined index: payment_address in /hsphere/local etc.

Why will it work for a guest checkout but not an actual logged in registered user?