Applies To:
  • CitectSCADA 4.xx, 5.xx

When you attempt to connect to a Windows NT Remote Access Service (RAS) server, you may receive the following error message:

Error Connecting to <RAS_server>. Dialling <Phone_number>.

Error 678: There is no answer.

You may receive this error message even though the RAS server is available.


This problem can occur if the RAS server you are attempting to connect to is configured to use Dynamic Host Configuration Protocol (DHCP) to assign remote Transmission Control Protocol/Internet Protocol (TCP/IP) client addresses, and one of the following conditions exists:

(1) There is no DHCP server on the network.

(2) The DHCP server on the network is unavailable.

To resolve this problem, use one of the following methods:

Method 1 -

Verify that a DHCP server exists and is available on the network.

Method 2 -

Configure the RAS server so that TCP/IP is not used as a RAS protocol.

Method 3 -

Configure the RAS server to use a static address pool to assign remote TCP/IP client addresses.

Note - The range of IP addresses must be valid for the RAS server's subnet.

Microsoft has confirmed this to be a problem in Windows NT version 4.0.