My PCI slot dial up modem only works once after i uninstall it (add or remove programs) and restart PC? After i hang up then try to reconnect i get an error 721 or 633. Have used modem troubleshooter but to no avail. Restarting PC WITHOUT uninstalling renders the same problem! Problem SEEMED to occur after installing Motorola phone tools program and plugging in mobile phone. Have uninstalled this programme completely and unplugged phone of course but still the same? Any help appreciated. P.S. I have used this programme before without ant drama? I reinstalled it as i reinstalled windows!