well, to add some more information here. In order to access our system, one must install our client software. So "permissions" on a client machine would not be a problem. just doing a login is not sufficient. We would like to bar "problem users" from getting on to our system. Some of them will purchase a new membership after we shutdown a problem account. If we could identify their machine uniquely, we could stop them from accessing our system. We could not stop them from using another machine, but blocking a single machine is an effective deterrant. We've used various "cookie" type mechanisms -- placing markers on their machine either in the file system or in the registry. All of these tactics are detectable, and may be circumvented (and have been). We're just trying to prevent a very small number of extremely annoying people from using our system. There are a lot of "obvious" ID's that people suggest, but don't really do much: - IP - doesn't work, cannot control dynamic IP users - MAC address - dialup users don't have a unique one With the new XP, Microsoft has started to employ the same mechanisms we seek... But they don't share stuff like that. Thanks
