Error 403 on creating subscription page

Hi I have to create a new subscription page but when I try to save it I have this message:
Forbidden
You don’t have permission to access / on this server.
I think I need to modify some folder/file permission but I don’t know where.
Anybody knows what must I do?
Thanks

Which version of phpList are you using please?
Also, what directory is your installation in?
If this is not root/lists then you’ll need to set $pageroot (in config/config.php) to match.

# if you change the path to the phpList system, make the change here as well
# path should be relative to the root directory of your webserver (document root)
$pageroot = '/lists';

Hi Dragonrider
thank for your answer
I modified the directory and I checked as you said
Everything is ok and the version is the
3.3.1
if I work in “config” and I try to update public header I have the same problem, it is ok if I update the public footer

@manisca what is your hosting environment?

I have seen similar problems when the hosting company has installed an apache module called mod_security, which has rules to filter and reject page requests. I had to disable mod_security in order to be able to edit the Settings page.

Hi duncan
thank for your suggestion
May be this is the problem becouse it is not the same if I try it on localhost
I 'll try to contact my provider and open a ticket about it

I red about this module that offers a protection against sql injection and more. I didn’t read code of any pages but I saw that when you make some changes into subscription pages you update db tables.
May be when you fill out the form you send a wrong string
May be is that the problem?

Solved
the problem was mod_security
Thanks