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Entry type: FAQ Entry ID: 18967416, Entry date: 06/28/2006

Why will the WinCC clients not communicate with the WinCC server?

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This may be due to the fact that the terminal bus has been configured incorrectly. If the computer has multiple network cards, for example, ensure that the correct network card is configured for access to the terminal bus.

Use the "Simatic Shell" tool to configure the terminal bus on all the computers involved, including the WinCC servers.

No. Procedure
1 Open "Simatic Shell"
Navigate through the Windows  Explorer to the Simatic Shell. You will find the "Simatic Shell" in the Windows Explorer under "My Computer > Simatic Shell". Right-click "Simatic Shell" to call up the pop-up menu and select the "Properties" entry.

The "Simatic Shell" was called "WinCC Projects" in versions of WinCC before V6.0 SP3. However, the procedure for assigning parameters to the terminal bus is the same.

You can find detailed information in the WinCC Online Help under "WinCC Information System > Configurations > Multi-User Systems > Remote Configurations".

2 Select the network adapter for the terminal bus
Select the appropriate network card in the "Network adapters" area which is used to access the terminal bus and check the network settings.

Fig. 01



  • The network card which is highlighted in blue is the card which is currently initialized for the terminal bus.
  • You can select a different network card by simply left-clicking it. When you click "OK", the "Initialize new" dialog window appears

    Fig. 02

    Click "Yes" to confirm that you wish to define the new network card as access for the terminal bus.
  • The IP address and network mask are actually assigned in the Windows Control Panel under "Start > Control Panel > Network Connections".
3 Check the "CCAgent" service
Go to "Start > Control Panel > Administrative Tools > Services" to check whether the "CCAgent" service is started.

Fig. 03


You can obtain further information on this topic in the WinCC Online Help under "Configurations > Multi-User Systems > System Behavior in Runtime > Special Communication features Using Servers with Several Network Cards" .

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