Paypal Standard API username, password, sig

[split63]

I requested and received an API username, password, and signature, but I don't see any instructions as to their use.

I don't see a place in Zen Cart for these.

It seems this info is for express checkout and not PayPal Standard?
What's the deal?

[DrByte]

PayPal Website Payments Standard is an older technology, and only uses your PayPal Account email address for submitting transactions.

PayPal Express Checkout is much more contemporary and more reliable, and uses the API sig/user/pwd as authorization credentials for protecting your transaction activity.
Instructions for setup can be found here: www.zen-cart.com/getpaypal