From the
BST Rules, a sticky at the top of this forum:
3.) To protect both the buyer and seller, we ask the following: You must post a valid ISP e-mail address that you can be contacted at, regardless of whether you are offering or requesting goods. College, ISP, Business, Home, etc. that allows us to get in contact with you are acceptable. Hopefully, we never will, but due to the fact that some people fail to follow through on their end of the bargin, we require this of everyone. Free e-mail services, like Hotmail, Yahoo, Gmail etc. are not acceptable. Failure to do so will result in the changing of the post by a mod/admin or deletion. If you do have a free e-mail account that you use more often than your ISP e-mail and wish to be contacted there, that's fine. However, it is still required that you have an ISP or other 'non-free' e-mail address. No exceptions.