Applies To:
  • CitectSCADA 5.30
  • CitectHMI 5.30

I am using dial-up networking and have set up the following modem configuration on my Windows 2000 machine in the Control Panel | Phone and Modem Options :

1. Modem Name: 'Standard 28800 bps Modem' attached to COM1 (the only modem defined)

2. Modem Properties:

Port speed: 9600

Flow control: None

Data bits: 7

Parity: Even

Stop bits = 1

I have made sure that the modem properties defined in the Control Panel are reflected in my Ports form in Citect. The Port number is set to -1 as it should be (denotes a virtual port). Immediately after starting the Citect Runtime, Citect generates an application exception at this point in the Kernel:

MODEM SERVER Line Device 7 'Standard 28800 bps Modem' found on COM1 configured as 9600 7 E 1

I know my modem configuration in the Windows Control Panel and communications in Citect are correct as I can run the same project on a Windows NT platform without seeing a GPF. What is causing the runtime to crash when running a dial-up project in Win2000?


This is a known bug in Windows 2000 where an attempt to query the name of a TAPI line device fails with an incompatible API version error. This problem has been fixed in Citect v5.30 Service Pack A.