Dear forum users,

I'm facing a weird trouble with an existing installation of wincc (one server, one client).

Both PCs are set with static IP, but sometimes I can't connect from the client to the server.

Restarting the server, I can ping it from the client, but as soon as AutostartRT is done, ping (on static IP) stop answering.

In the mean time, ping from server to client is okay and does not stops.

Firewalls are stopped (win 7 32bits), and no antivirus are running.

Sometimes after rebooting server, client can connect, sometimes not.

Sometimes client can connect after a while the server is running.

Both PCs and PLC are on a isolated network (physically) and doesn't show any suspicious process running.

This installation is running from more than 10 years, and the client always had trouble reconnecting client to server.

Versions info :

Any advices ?

Hi -dFx-,

I understand that server and client have exactly the same version of WinCC installed, including SP and Updates, right?

The version of STEP 7 V5.5. SP3 is not compatible with WinCC V7.0 SP2, so it might be advisable to install ServicePack 3 of WinCC V7.0, which does support this compatibility.

It is important that the terminal bus (Server-client) is separated from the plant bus, each bus with its own network card, to avoid connection problems.

I would also check the compatibility between WinCC and the operating system of the server PC and client PC, using the tool below:

Welcome to the compatibility tool

Finally, the points indicated in this FAQ must be met: What are the requirements for operating SIMATIC WinCC in a Windows network?