Unable to verify POST vars. please contact support for assistance

HTTP replaced with H - - P and HTTPS to H - - PS because new users can’t post more than 2 links. Sorry for this.

Hello everyone, I’m trying to launch my website to get some income. And everything is ready. The only missing part is the actual cash-income configuration using Clickbank and S2member.

It appeared to be simple… until errors came up. I need to launch this, this week. Can you help me?


According to this scanner, i shouldn’t have any error.

When a user purchase by clicking this link ► h–ps://cnscientia.pay.clickbank.net/?cbitems=1
which is the URL Clickbank gave me for the product, i can use my test-credit data to simulate purchase.

it completes, and sends me to the thank-you page. But when i use the s2member code:

It says “unable to verify POST vars. please contact support for assistance.”.

and this guide “h–ps://s2member.com/kb-article/why-am-i-seeing-unable-to-verify-_post-vars/” is not helping me. the server check is all green, and there’s nothing else there to help me. Clickbank is not in the list.

What am i missing here?

thank you guys! please help me!
Attaching at the end of this post, log files: http://waveprinciple.net/wp-content/uploads/log-file.txt

p.s. also, how can i prevent this other issue? I tested my website and it’s possible that unknown users buy the product, but they haven’t created a user yet (user level 1, there’s free content for free members account). The product access is supposed to be attached to their account, so when they buy the product they account gets promoted to user level 2 (premium).

Hi Eduardo.

I will help you.

I see in your logs that the s2 ClickBank notify URL in some entries say 1 and in others 6. It has to match the version that you have in your CB account. Which version of the CB IPN did you set in your CB account? Account Settings > My Site > Advanced Tools

If you just go to the notify URL in your browser, you’ll have missing vars because that address is meant for ClickBank to load it, and it would include variables that s2 is expecting from CB. Those variables aren’t present if you just load it on your browser.

Did you go through the whole configuration of the integration, on s2 and CB sides? Did you verify that you entered everything correctly? If you did, did you test a purchase to see how ti goes?

After you do that, please tell me all the relevant details, and include screenshots if you want (blurring the credentials).

I look forward to your update. :slight_smile:

Hello! Sorry for the late (ultra late) reply… this error came back again.
This time i managed to record a video, and it’s weird. because it was working fine.

then i migrated to a new hosting server and it got broken.

i did all the fixes required, and noticed the “thank you page” url in clickbank was using %D5 something like that instead of slash /

fixed that, and it worked once. i was relieved.

then i retested it and the POST VARS error showed up again… i dont understand. I can’t use IPN v 6, so it’s using v 2.1 …

what else is happening to make this error occur?

here’s the screen share

Hola Lito.

I remember your site, I troubleshot this in the past more than once and got it working.

Back then the problem was your upwork freelancer repeatedly not using s2’s shortcodes for the CB button, and misconfiguring the s2-CB integration.

It’s odd that you keep getting it back after a while. Apparently some changes on your site bring it back…

This time, from what I see on your home page, it appears to be using s2’s shortcode, but I need to verify it, and go over the configuration and logs.

I’d like to take a close look again, do some test purchases, etc. I should be able to find again what’s going on. I’ll need logins to wp-admin and clickbank again, you can message/email me those if you agree.