We have a site build around Community Builder for registrations.
For the longest time we were having tons of spam registrations and couldn't figure out where they were coming from. It turns out they were coming all from bots or spammers using K2 to register despite that this wasn't turned on.

Finally when we used the url: www.oursite.com/index.php?option=com_users&view=registration
we found the registration form that was being used.

If we turn off the user registration as was detailed in another forum post (www.joomlaworks.net/forum/k2-en/40959-solved-how-to-disable-new-k2-users-registration#142733)

then we found that this prevents this registration from showing but also prevents our Community Builder registration to work.

Is there anyway to prevent registration through K2 to stop showing up at this URL above and yet not disable the normal registration through our site?

Thanks.

This is Joomla!'s default URL for registration.
With K2 or without, this URL is still being used. You can enable Akismet, stopforumspam and/or enable reCaptcha to block these users to register to your site.

Yes - I understand.

Seems like there should be a plugin to redirect this page always to the regular registration as I really don't like any page public that allows any bot or human the ability to bypass our normal registration questions etc.

Also, I don't get why bots seemed trained on these pages that aren't even public. I'm guessing adding akismet or stopforumsspam or recaptcha doesn't really stop this "traffic" on your site.

I have enabled reCaptcha and Akismet.
My spam registrations have gone down, however I still have an occasional spam registration.

Isn't there anyway to totally disable this page so that it doesn't exist. Seems crazy that I can't force them at least to use the Community Builder registration that is setup. The fact that a "registration" comes up on this page makes it possible. I'm guessing they must be filling out the reCaptcha which I assume means they are a real person.

Also, the way I read it is that Akismet only is for comment spam and doesn't really help with the registration spam. Am I wrong on this?

Bots are trained because these URLs are common for millions of Joomla! powered sites.

Same goes for Wordpress / Drupal URL patterns.

You can try a permanent redirect to the CB page, but I do not know if that would affect the registration process.
You can look at the JED for an extension that does this.

Furthermore, if they are real persons, the best thing to do is to disable manual activation so they will not be able to post content on your site.