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AE unsubscribe re-subscribe

23 Oct 2019 16:13 #7863 by support
Replied by support on topic AE unsubscribe re-subscribe
I need the version number, and also a build number of the QuickOPC assemblies you are using please.

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23 Oct 2019 15:17 #7859 by fancybird
Hello ...

I searched and saw a post on this exact topic in 2014. Forgive me ... I am going to ask again ... with my own specifics.

We write a tool to subscribe to AE to capture a "current snapshot".
When we are done, we un-subscribe.

A few minutes later, we want to subscribe again.
We don't get any Exception.
But new alarms / events will not show up anymore.
And we do a manual refresh, the application freezes.

We tried both Unsubscribe() and UnsubscribeAll(). No difference in outcome.

Please note that it does work sometimes. Most of the time, it does not work.

We do put in a 10 second timeout after un-subscribe, before the user can re-subscribe.


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