Siemens Industry Online Support
Siemens AG
Entry type: FAQ, Entry ID: 1014417, Entry date: 03/07/2011

Why can the WinCC uniclient not open the project from the server?

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The project is supposed to opened by the WinCC uniclient (client without its own project) from the server. But you cannot open or activate the project. On the client you get a message that no connection can be set up to the database server. If this error message appears, then this is due to the link between client and server.

Check the following:

No. Procedure
1 In WinCC "Multi-user system" must be set in the project properties. All computer names (server and all clients) must be entered under "Computer" in the WinCC project (on the server).
2 Select "Start > Settings > Control Panel > Network Connections > Your Network Connection > Properties > Internet Protocol (TCP/IP) > Properties". If the "Take IP address from a DHCP server" function is activated in the "IP Address" tab, then such a DHCP server service must also be available in the network. This means that a computer or a network component must be installed as DHCP server. If this function is not activated, select the "Use following IP Address" function. You must assign an IP address to each computer.

If you are using Windows Vista or a more recent operating system, you obtain the properties of the network connection by way of the "Networks and Release Center" in the Control Panel.
3 Open the input prompt (Start > Run... > cmd) and execute the "ping + IP address" command (for example, ping for each other computer.
If you do not get a response, you must check the complete network configuration and parameterization.
4 If the network test works by way of the IP address, you must now change the "lmhosts" file so that the computers can also be reached by way of the computer names. This step is only necessary if you do not use a DHCP service in the network.
The "lmhosts" file is in the path below in Windows: <Drive>\Windows\system32\drivers\etc\. Open the file with the text editor and enter all the computers that can be reached in the network according to the example in the file. Then save the changes in the file.
Make these changes on all the computers.
5 Open the input prompt (Start > Run... > cmd) (Start > Run... > cmd) and execute the "ping + computer name" command (for example, ping WINCCPC01) for all the computers that you entered in the "lmhosts" file in the previous step.
If you get a response, then the file has been configured correctly and name resolution works in the network.
6 Use the file explorer to test whether you can access the project drive of the server.
If not, then install the releases on the server.


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