* Warning * Payment processors such as Paypal have strict rules regarding what it can be used for. Accounts have been frozen when the rules have not been followed. Some reports in the press incorrectly used the word "autosurf" when describing a particular scam and the same is adopted by the SEC and Paypal. If your site mentioned this word it's possible Paypal would freeze your account. When writing the text for your site avoid using autosurf, investment or other similar words. Check the terms and conditions of your payment processor to make sure your site complies with their rules.
A payment processor such as Paypal and Alertpay will handle payments made by your customers and automatically update their accounts with their purchase. You can use any payment processor and manually update their account using the easy upgrader (BCP --> Membership Options --> Easy Upgrader).
Setup Paypal
There are two tasks to perform, first login to Paypal and make sure IPN is enabled, then add your Paypal business email address to your profile. Note that you must have either a Premier or Business account to use the IPN facility. If you have a personal account you can upgrade to Premier free of charge (at time of writing).
lets start by setting up Paypal IPN, to do that follow these steps:

NB. If you already have IPN switched on for another website then you have nothing more to do. Each time this website sends a payment it also sends instructions to Paypal for handling this transaction separately.
Now lets add your Paypal email address to the BCP, to do that follow these steps:
Setup Alertpay
Alertpay uses a similar method of IPN to Paypal with the addition of an Encrypted Security Code. Here's the process for setting up Alertpay:
Now return to your BCP to complete the setup:
* Note * There have been reports where the Encrypted Secret Code will not work correctly if it includes a + sign. For example if yours is o+/mEt1wsn9PWk5bIKxtwx it may not work if you just paste it in. To fix this problem replace the + with a single space so it looks like this: o /mEt1wsn9PWk5bIKxtwx
To further complicate the issue we know that sometimes this will work either way! The best thing to do is try it as provided top you by Alertpay and if that fails do the replacement and try again. See the section on testing your payment processors below.
Whether Paypal or Alertpay there really is only one true way to test end to end to ensure they work correctly. Find someone with another account and ask them to signup and make a payment. They can cancel the subscription and you can refund the payment when the test is complete and this will not incur any charges.
There is support for making payments by any payment method using the Easy Upgrader, click here for more information on this topic.