We have a system hosting many websites for our customers, and inside that system there is a method that non-live customers can view their sites before we turn them on. Say the link is something like this: ourbigcompany.com/customer/domain=thisisanewsiteurl
Those links are not linked to anywhere outside a secure login - they are only sent to the customer via email. They are publicly viewable, as they have to be, but that's not the real problem. The real problem is that somehow Bing is getting hold of them and trying to crawl the sites. I know how to stop the crawling, but that would be like treating the symptoms without fixing the problem.
We log the traffic and there is no referrer - so that is not helpful.
If I change the querystring value for a site, Bing has it within hours. I need to figure out where Bing is getting the links from so that I can close what is obviously a security hole, but I am not sure how. Any ideas on how to figure that out?