Cant Install Addons

[Xenoo]

I cant install certain addons, like I have some addons installed but than I cant get some.

 

Whenever I go to (Setup > Addon Modules ) it says "You can't access this file directly..."

 

It brings me here http://www.xenoohost.com/client/admin/configaddonmods.php.

 

It lets me go here http://www.xenoohost.com/client/admin/addonmodules.php

 

but I cant go to the other page.

 

I uploaded all the files to this one addon and when I go to activate I get the same error and it brings me to here.

http://www.xenoohost.com/client/admin/configaddonmods.php#actwhmcs_autoloader

 

Please help me out.