users can't register because captcha is ...

Hi all!
When users trying to register at my site, they can't because captcha is not working and when I tried to copy the image location and look what the error the error is:

Undefined variable: bbox (#8 ) in /functions/gd.php on line 157

The GD is fine, I talked to the admin of the server and he checked that the GD library is OK and it's do.
can I remove this option of captcha at all? I don't need it any way.

Thanks!

justoneguy

Somebody on the forums reported that they disabled it by simply removing it from the templates.

I suspect you're using an older version of GD as this is the first time anybody reported this error.

and how can I set permissions for downloads, like that unregistered users cannot see links of HTTP?
Thank you

You'll have to hack the template files for that. See templates/skio/file.tpl.php for file listing template.