Connection freeze|OPC UA Standard|Forum|OPC Foundation

Hello,

We have developed an OPC UA client using .NET Standard UA SDK running on Win10 Pro. It connects to an OPC server, subscribes to nodes changes and starts to monitor them.

At one installation we have a really weird problem. The OPC server has to be turned off every night for about an hour. After being online again, no values are coming into our app. In the same time, the connection to server runs without any errors. Even more, if we restart the connection, meaning close an existing session and create a new one, it doesn't start to work.

We have added a polling mode instead of using subscriptions and it didn't help. Only the restart of our app helps.

It seems that all sessions within a single process are freezing somehow without any error after loosing a connection to an offline server.

Meanwhile we tried to reproduce this with simulation OPC servers (one from UA SDK sample and UaCpp from Unified Automation) running on the same PC as our app, and it always worked as expected.

Any ideas?