paypal standard with other checkouts, catch 33

I'm trying to get Zencart paypal standard payments IPN to work, as well as 2 checkouts from another provider. I have 2 sites running paypal already using oscommerce and I cannot enable IPN because it is enabled automatically by the software and the URL's are different. It seems that if I enable and put in one URL it will screw up the other one.

Now, add Zencart on my 3rd site to this also - I'm finding that every solution has a problem. If I'm getting this right then Zencart needs to have IPN enabled (although it doesn't matter which URL since Zencart sorts it out for you) - but I can't put in any URL since it will stop one of the other sites working properly. Paypal will not let me set IPN to on without adding a URL...
I'm looking at these possibilities:

1. If Zencart can run by submitting the URL return information itself on the fly then there should be a way (I hope) to enable IPN automatically from Zencart without having to set it in Paypal at all (the oscommerce checkout system for Paypal IPN does this). So can anybody direct me to where this can be achieved in the coding for Zencart and how to code it with an amendment or addition.

2. What happens if I don't enable IPN at Paypal at all - your instructions say that it must be enabled, but is this just playing safe ?

regards

Simple: use Express Checkout instead. That way you don't need to rely on IPNs to tell your store about new orders.

"Simple: use Express Checkout instead. That way you don't need to rely on IPNs to tell your store about new orders. "

I dont want to do that - I knew it was an option but I regard any data sent to a site and kept on it as unsecure whether it has SSL or not. I really don't want to go into details of why or wherefore Express Checkout but need an answer to my problem.

It's not always the case that 'in one bound Jack was free' with an easy answer.

Is there a way of doing this?

regards

catch33:

I dont want to do that - I knew it was an option but I regard any data sent to a site and kept on it as unsecure whether it has SSL or not.
I have no idea what you're talking about.

PayPal Express Checkout is the SAME SERVICE as PayPal Website Payments Standard, just implemented differently, and in a way that works much more reliably than waiting on IPNs.

So your comparison is moot. So is your SSL statement.

Ahhhhh...
I got confused by the Paypal website and thought the credit card bit (which is done on customers website) was part of the Paypal checkout (which can include credit card via Paypal). My mistake and thank you Sir.
:oops:

Having now looked at Paypal xpress setup you are right it is exactly the same - and it has same problem. For my other 2 sites on oscommerce you musn't set IPN to enabled on Paypal site and on Zencart you must set it to enabled.

So I need a way to get Zencart to set this on the fly instead of enabling it in Paypal myself.

I get the feeling that Zencart is meant to be more standardised then oscomm (i.e. less interference by users) - which I understand the advantage of, so I'm not sure that I will get a solution...:wacko:

You're completely misunderstanding things, and I'm rather disinterested in embarking on writing a novel about how all the technology works.

I'll abbreviate grossly:

a) Set up Express Checkout as per the instructions, including enabling IPN and pointing it to your Zen Cart site as instructed.
b) Your other sites will ignore the IPNs because they'll never see them.
c) Zen Cart will receive all the IPNs and will ignore the ones that aren't intended for your Zen Cart site.

Simple.

Or, if you wish to be stubborn about it, just leave the IPN setting off. That will satisfy your other sites' odd requirements. And since Zen Cart doesn't need the IPNs for processing incoming orders, there will be nothing lost there either. The only thing you'll miss out on is the ability for PayPal to tell your Zen Cart site about refunds or other changes to transactions. Clearly your other sites aren't capable of that right now either, so you won't even know what you're missing out on by using less-featured products for your other sites.