My settings is set correct. In Admin -> tools -> send mail is working good. All massages going fine. But if I whant to crate a new accaunt I have an error "Email Error: SMTP Error: Data not accepted." What is it? And why my email sending working good in Admin -> tools -> send mail?

It is something with Zen Card or what? My version of Zen Cart is Zen Cart 1.3.8a

PHP Version: 5.2.6 (Zend: 2.2.0)

Any body know how to solve a problem?