I read that Twitter can blocked OAuth app in a certain IP. The question is whether the lock can be at the domain level . I have two web pages hosted on the same server with the same IP. I work well in a an app Twitter and other not. I have reviewed and adjusted all parameters, including the login callback and I confirmed my feeling. In a domain it works well and not in another.
Even if an app that works change parameters: Website and Callbacklogin and domain change stops logging new users. If I return to the previous domain parameters the app again work well.