Not sure if this fixes it, but this (cforms.js):

var sajax_uri = 'wp-content/plugins/cforms/lib_ajax.php';

should be:

If I look at your HTML it shows me that the URL the webserver understands always starts with:

http://fortuda.be/blog/VerdienenMetGPT/....That's why I suggested to put this into the js/cforms.js file, as outlined above.You still have the wrong path in there, that's what currently breaks CAPTCHA reload.

I have as wordpress adress: http://fortuda.be/blog/VerdienenMetGPT

i have as blog adress: http://blog.fortuda.be

and I have created a subdomain blog.fortuda.be with document root : /public_html/blog/VerdienenMetGPT

but that should be correct? The wordpress works…

I have added a slash in abspath:

<?php $abspath = '/home/phil/public_html/blog/VerdienenMetGPT/'; ?>

I have in cforms.js:

var sajax_uri = 'http://fortuda.be/blog/VerdienenMetGPT/wp-content/plugins/cforms/lib_ajax.php&#39;;

Does it use sessions and cookies,

maybe subdomains cannot share it with the parent domain?

Yes that is true,

because my subdomain document root is : http://fortuda.be/blog/VerdienenMetGPT

So when you enter that url you will automatically get fortuda.blog.be/blog/VerdienenMetGPT and does not exists because in the structure it looks like http://fortuda.be/blog/VerdienenMetGPT/blog/VerdienenMetGPT

maybe a fault :s ? But it is not the intention to enter fortuda.be/blog/…

But the url http://fortuda.be/blog/VerdienenMetGPT/wp-content can get through,
I'm just getting more confused.

EDIT: That error you gave has been fixed by doing the following :

var sajax_uri = 'wp-content/plugins/cforms/lib_ajax.php';

I also tried to put this on top of the page:

ini_set("session.cookie_domain", ".fortuda.be");

but still not working

I have been doing some test for cookies and I found that
if I display   <?php print_r($_COOKIE); ?> on my main page of my blog that their is only a "check test cookie" saved.

If I display   <?php print_r($_COOKIE); ?> on my admin page,
It displays the test cookie and myself admin login.

Shouldn't that login cookie also be displayed on the mainpage? Or is this different?

I was thinking about this because when you disable "Force CAPTCHA display for logged in users" then there is still a captcha field on the contact page…

EDIT: I FOUND IT !! /D

Its a problem on your side ;) on the cforms captcha.php

You'll have to update this dude,
Check your setcookie() ;)

I have changed it in :

setcookie('turing_string_'.$no, $_REQUEST['i'].'+'.md5($tu),(time()+60*60*5),"/",".fortuda.be");

Finally, I thought I would never found it :P

If you want to contact me use the contact page ^^ :p

http://blog.fortuda.be

Here's the solution to this problem..:

Change:

setcookie('turing_string_'.$no, $_REQUEST['i'].'+'.md5($tu),(time()+60*60*5),"/");

To:

setcookie('turing_string_'.$no, $_REQUEST['i'].'+'.md5($tu),(time()+60*60*5),"/", $_SERVER['HTTP_HOST']);

In:

cforms-captcha.php, around line 54.

In my case, captchas worked fine in IE, but failed the "smell test" in Firefox. The cookie returned from Firefox was always empty. Above code works in IE and Firefox.