our new winform app will be licensed on a per user basis. but how can i prevent multiple people from logging in concurrently using the same username and password?

i realise this is probably an aged old question. but i am grateful for any advice on how to best implement our licensing strategy. thanks.

You're really not telling us enough here. If there is a central server to which all clients are logging in, then it would seem simple enough to have the server keep track of which clients have logged in and with what credentials, and have your app send a logout to the server when it closes.

If this is a stand alone app with no interoperability among the clients, then you may want to add a registration key feature to it where each client must get a unique key, either by having the client contact a web server you manage to get it in exchange for some unique bits of information from the client computer so it can't be copied to others, or requiring each user to register online someplace to get a key they install into the app.

Eventually you'll have to deal with users getting computers replaced, re-installs, lost keys, etc. Revoking the previous license in these cases becomes the challenge. Maybe your app can periodically call out to your web server to validate the license it has. InstallShield may have a solution that fits your needs.

Chris

You're really not telling us enough here. If there is a central server to which all clients are logging in, then it would seem simple enough to have the server keep track of which clients have logged in and with what credentials, and have your app send a logout to the server when it closes.

If this is a stand alone app with no interoperability among the clients, then you may want to add a registration key feature to it where each client must get a unique key, either by having the client contact a web server you manage to get it in exchange for some unique bits of information from the client computer so it can't be copied to others, or requiring each user to register online someplace to get a key they install into the app.

Eventually you'll have to deal with users getting computers replaced, re-installs, lost keys, etc. Revoking the previous license in these cases becomes the challenge. Maybe your app can periodically call out to your web server to validate the license it has. InstallShield may have a solution that fits your needs.

Chris

There are several products that will help you meet your requirements.

I would recommend Quick License Manager.

See: http://www.interactive-studios.net/products/qlm.htm