Hi guys, I'm facing strange problem. I have SIMATIC NET OPC Server installed on one PC A running windows 7 and I configured firewall and other properties as it is described in pdf file that comes with Simatic net v13. When I try to access this OPC server via OPC scout through PC B that is also running windows 7 I can do that without any problems, this situation was like a week ago. Then it is decided that we will replace PC A with a new PC that is also running windows 7 and repeat all configuration that has been done once again. Now the problem is that a OPC client that runs on Windows server 2008 can't access this new OPC server, but the PC B can,in a matter  fact, PC B works just like nothing has been changed. 
I know is weird situation, the Windows server 2008 worked a week ago and now it doesn't, and I know that you are going to think that the problem is in configuration, but the old PC A, new PC A and PC B have the same configuration and the firewall is down.
I have no idea where to even search for the solution.

Edit:

When I installed simatic net on the windows server 2008 r2. I have generated xdb file with right name and ip address for the windows server 2008. I tried to run it on the station configurator, it says that the everything is fine, but in opc scout every tag is not ready everything is red color and in PLC network I can see that there is no connection to the opc server. In case that everything is the same but station runs on windows 7 opc scout works normally and there is no problems at all.

Did someone tried to install simatic net  v13 on windows server 2008 r2 and succedded in doing so?

I forgot to say that I have RPC error in OPC scout when I try to connect to Simatic NET from Windows Server 2008. 

Hello dolbyinside

Which OPC Specification do you use? OPC DA, OPC UA?

-> If you use OPC DA check if the Name resolution is working and if the DCOM Settings are OK.

Use for testing with same Windows Login accouts on both Systems

-> If you use OPC UA which Security Settings do you use on OPC Server and Client?

Bye Murof

I think that we are using opc ua, byt I'm not 100% sure, is there a way to check which specification is used?

I followed the instruction on DCOM settings, but I will check it again

Hello dolbyinside

hm .. the simatic Net OPC Server in an up to date Version can use both OPC UA And OPC DA.

It depends on which OPC Server you connect.

for example if you want to use OPC UA then you have to use a communication setting in the Client like this:

opc.tcp://Servername:Port

And you have to set Security Settings.

For OPC UA you do not need DCOM.

Bye Murof

Oh, in that case I am using OPC DA, since I need to configure DCOM. Right now the there is some problem with network card on the Windows server 2008. Something is not right since this is second time this week that network card failed(the one that last time failed was on the OPC server).

Thanks for the explanation, I have seen that there is a OPC UA and OPC DA server when I used OPC scout.

I will keep you posted if there are some changes or news after we deal with the network card problems ;)

Hello dolbyinside

Thank you for your reply.

If I had the chance I would always use OPC UA, instead of OPC DA, Because there are a lot of Advantages in OPC UA. For Example:

- No use of DCOM -> you do not have to use Windows Operating System

- Timeout Management and Error Detection in Communication

- Real Security

- Possibility to access over Firewalls and Internet

- Web Based Applications

You need only an open Port and no error-prone DCOM Settings

Have a nice Day

Bye Murof

New question published by enof is split to a separate thread with the subject opc ua under non-windows for s71x00 symbolic comms .

Best regards
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