1. Select the "Start > Run" command. This will run the "dcomcnfg.exe" file.

2. Open the path "Console Root > Component Services > Computers > Workplace > DCOM Configuration.

3. Click "Yes" in the registry dialog boxes.

4. Select "OPCServer.WinCC" and open the properties dialog box.

5. Select the authentication level "Connect".
   

   Make the additional settings as in the WinCC Description mentioned above.

   Under Windows XP, the local security policy for network access is set in the WinCC setup. This setting should not be changed.

   Select "Start > Settings > Control Panel > Administrative Tools > Local Security Policy > Local Policies > Security Options".

   Select the "Network access: Sharing and security model for local accounts" policy and then set "Classic – local users authenticate as themselves".

Thanks again for replying Irmantas.

I go truesettings you recommended and they are OK.
I also find Error log for OPC (C:\Program Files\SIEMENS\WinCC\OPC\dataaccess\bin), but I don't know what it means. So I made aPrint Sreen of error, andattached it to this message. I hope you could help me.

Thanks.

IrmantasI solve the problem.
I copy all the screens and tags into another project and now the OPC is working. (I still don't know were was the problem, but for now I am satisfied with solution).

Thank you very much for yourhelp.