The ISDN CAPI Port Driver creates "virtual modems" in the system which can be used by all applications that are designed for use with analog modems with the AT command set (such as Dial-up Networking, HyperTerminal). The CAPI Port Driver also permits the use of applications that require a conventional COM port.
Fix for Windows XP Service Pack 2 (Installation)
It is highly recommended to always use the most recent driver version available.
Do not forget to check with our site as often as possible in order to stay updated on the latest drivers, software and games.
Try to set a system restore point before installing a device driver. This will help if you installed a wrong driver. Problems can arise when your hardware device is too old or not supported any longer.