If you have just bought a Samsung 46” LED and are having trouble setting up the Internet@TV ID then you should keep reading.
When setting up the Internet@TV you might experience that the accounts disappears when you try to sign in. The problem might be caused by an incompatibility between the latest Internet@TV software and the firmware of the TV. When you first access Internet@TV the software is automatically updated, if you have not already updated the firmware of the TV to the latest version you might experience this problem.
To resolve the problem go to the Support menu->Software Upgrade and upgrade the firmware of your TV. To avoid the problem altogether upgrade the firmware before you access Internet@TV.