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Internal EasyOpcUA error on large amount of monitored items

15 May 2024 13:47 #12789 by ToSi

updating the software solved the issue. Thank you very much.

Best Regards

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13 May 2024 15:50 #12782 by support

This looks like a problem on the client (QuickOPC) side. However, it is in an old version than we no longer officially support - and make no fixes for.
The recommendation is to test with the recent QuickOPC version. We will investigate if the same issue appears.

Best regards

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13 May 2024 14:04 #12781 by ToSi

we just increased the amount of subscribed signals within our OPC-Client. Now most, but not all items don't receive data change events. The Subscription event listener does not notify us about any exceptions but the Windows event viewer does:
Internal error (only first occurrence is logged): An exception of type "System.NullReferenceException" from source "OpcLabs.EasyOpcUA" has occurred in OPC-UA guarded operation 'ConnectSubscriptions'. The exception descend follows.
(0) System.NullReferenceException OpcLabs.EasyOpcUA (AddMonitoredItemsToSdkSubscription) -> Object reference not set to an instance of an object.

I am not able to make it work, even when decreasing the amount of signals again, which is very strange. We talk about 1000 signals with this client. Could it also be a server-side problem?

SImilar topic: NullReferenceException on Large Subscriptions

OPC-Server: Siemens PCS7

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