403 error, can't access login.php with redirect

[ucdcrush]

Hi all, I am having a problem with a site I am putting together. I have an area of the site that is for registered users only, so if someone who is not logged in visits the home page and clicks on a page viewable only by registered users, there is a 403 error.

Of course it should take them to the login page, and once they are logged in, redirect them to the page they intended to view.

If I remove the ?redirect part, the login page itself works fine. Does anyone have an idea what could be wrong?

[ucdcrush]

I contacted the host support and they fixed it, saying:

"I had to whitelist one of the mod_security rules that your script was hitting."