Was it paypal express? there is a setting in the admin panel that deals with an account being automatically created if the customer doesn't already have one and this can be set to true or false. Have you tried changing it to false?
Regarding resetting the password, can't the customer click the "forgot your password" link on the login page? It should email them a new password. If that doesn't work for any reason, have you tried the mass reset customer password mod? You reset their password by inserting a mySQL statement into you database through phpMyAdmin. Here's the link:
http://www.zen-cart.com/index.php?ma...roducts_id=531
You just need to look up their customer ID in the admin/customers panel and insert that into the SQL statement along with the new password.
Let me know if that sorts it out for you. I think that everyone the uses paypal and COWA will run into this problem.
Matt




