I have a private blog with users who have registered correctly. Two of these users cannot access the blog. They have given me their login ID and password and when I try it it works fine, but when they try they get a "page not found" error.
Users can log into wordpress.com without a problem, then they see the link to the blog, but when they click the link they get "page not found". So, they can see the link, but can't get in.