How to change default directory?
I don't want to use the default long URL:
http://www.website.com/webform/webform.html

Instead, I prefer to use:
apply.website.com

Any idea on which files I must modify?

thanks in advance

That is not something you would do in Form Builder. That is done on your serve by uploading the files to the root folder and not the sub-folder "webform".

yeap, but still need to make reference to webform.html, otherwise, I get an error

Any idea how to rename webform.html
and use index.html instead?

Just rename it. As long as the markup references the correct files and paths, the actual name of the HTML file can be anything you like.

This is the error I get when I put everything together in sub-domain root directory (aplicar.website) and then rename webform.html for index.html:

Warning: require(/home/website/public_html/aplicar/webform/fbapp/php/config.inc.php): failed to open stream: No such file or directory in /home/website/public_html/aplicar/webform.php on line 6

Fatal error: require(): Failed opening required '/home/website/public_html/aplicar/webform/fbapp/php/config.inc.php' (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/website/public_html/aplicar/webform.php on line 6

What is the direct URL to your form?

http://aplicar.website.com (website is an example, I do not want to reveal my real domain here in public)

I need to see the URL to help you diagnose the problem. If you cannot share that, there can be 2 possible issues here:

1. This issue could be caused by permissions not being properly set on your server. With an FTP client, locate the folder called storage and change the permissions for that folder and all folders under it to 755. That should then fix the issue.

2. That could be caused by PHP Sessions not being enabled on your server. All you need to do is contact your hosting provider and have them enable PHP Sessions and your form will start to work.

Alternatively, if they cannot enable PHP Sessions, you can publish to S-Drive as our servers do have PHP Sessions enabled.

storage Folder is 755, and all its sub-folders.
Could you please give the line code to paste it in .htaccess in order to enable PHP Sessions?

Btw, the form works perfect if I use the default directory structure (webform/webform.html)