When a customer creates an account or logs in, s/he is offered the option (a "Remember Me?" checkbox) to be automatically logged into your website on subsequent visits. If the customer checks this box, a cookie is set in the customer's browser; that cookie's name is zcrm_xxxx where "xxxx" is an MD5 hash of your store's name (as set in Configuration->My Store). That cookie remains set (and provides a continued-login to your store) until:
zcrm_xxxx
Security Note: The customer's password, as stored in the cookie, is a hashed version of customer's Zen Cart hashed password value, so the customer's actual password or password hash is never exposed.
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