Question

I’m wondering how to forbid access to the all directories except one using .htaccess file.

The construction like

<Directory />
    Order Deny,Allow
    Deny from all
</Directory>

<Directory /folder>
    Order Deny,Allow
    Allow from all
</Directory>

raises Error 500. It can be put only in apache conf file, right? Or I’m doing something wrong?

Answer 1

The Directory directive may not be used in a .htaccess file (see the Context section of the Directory docs). From within a .htaccess file you can use Files or FilesMatch as a section container, or mod_rewrite. Assuming you’re allowed to use mod_rewrite (and you have a good reason for using a .htaccess file in the first place, like say, you’re not the server admin):

RewriteEngine On
RewriteRule !folder [F]

In principal this answers your question. It’s more likely though that your situation is more complicated than you’re letting on.

http://httpd.apache.org/docs/2.2/mod/core.html#directory
http://httpd.apache.org/docs/2.2/mod/mod_rewrite.html#rewriterule
http://httpd.apache.org/docs/2.2/sections.html

BTW, this question probably belongs on serverfault.com