Applies To:
  • CitectSCADA 5.31

IDC in CitectSCADA v 5.31 and TCP/IP do not Work under Windows 2000 SP1.

Errors include:

    Cannot Open Server XXXXX

    NetBIOS Error 0

    Cannot open IPC mode 16


Citect version 5.31 includes several new drivers, one of them named ICMP.DLL. However, the driver ICMP.DLL has the same name as a Windows DLL which is a critical part of the TCP/IP protocol. The Windows DLL is part of Windows 2000 Service Pack 1.

This problem will prevent Citect from running as an Internet Server for the IDC Client and stop any PLC protocol driver which uses TCP/IP as its transport. It will also prevent CTAPI from working over a network as it also uses TCP/IP (you will get error "Cannot open IPC mode 16" in the Citect Kernel), as well as preventing Citect Client/Server communication if you are using [LAN]TCPIP=1 in the CITECT.INI file.

You may work around this problem by renaming or deleting the ICMP.DLL in the C:\Citect\Bin directory. This problem has been fixed in Citect version 5.40r0 and higher where the driver has been renamed to CTICMP.DLL.