Hello,

I'm developing a redundant scada system with WinCC Professional v15.1.

From engineering station, when I try to download project, I get following error:

"Download to the single station cannot be performed when only one PC of the redundant servers is active".

From Simatic Shell I can see all my 3 machines (2 servers and engineering station), from all 3 machines.

What can I check?

Thanks in advance.

Got the same message on a production system if the redundant, or both default master and redundant are online.

If only default master is online, I can download to the redundant. 

Any idea why or how to diagnose? The usual suspects (configuration, IP, name, network) are ok. Will I have to reinstall the system? V17.

I tried to comb through the logs/diagnose but couldn't see anything related.

Running Reset_WinCC.vbs script on the default master "cleared" whatever it was (server restart didn't clear it) and allowed the download to server. Maybe a process/service was unresponsive to requests from Engineering. Firewall was already disabled.