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BrowseDataNode doesn't works anymore on 2019.2

05 Nov 2020 16:35 #9076 by support

this problem is not related to certificate of the server you are connecting to. You can revert the changes you made with CertificateAcceptancePolicy etc., they have no effect on this.

The problem is also not related to just Browse; it would occur with any OPC UA operation. The issue has to do wit the UA certificate of the client application (your program).

First thing to try: Run your EXE once with elevated (administrator) privileges. It might be trying to manipulate the certificate stores but fails to do so due to lacking permissions.

If that does not help: Check the contents of C:\ProgramData\OPC Foundation\CertificateStores\RejectedCertificates\certs and see if there is a certificate that corresponds to your application, and if so, move it to C:\ProgramData\OPC Foundation\CertificateStores\UA Applications\certs .

I hope this helps.
Best regards

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05 Nov 2020 11:04 #9073 by alr1976

I have used 2018.2 for long time.(Delphi) Now i have changed in 2019.2 (I need support for Windows 7 again).

i have function to read root in my opc ua server but in 2019.2 doesn't works anymore.... Give me certificate Problem.

My function:

BrowseParameters: _UABrowseParameters;
BrowsePathParser: _UABrowsePathParser;
Client: TEasyUAClient;
Count: Cardinal;
Element: OleVariant;
EndpointDescriptor: _UAEndpointDescriptor;
NodeDescriptor: _UANodeDescriptor;
NodeElement: _UANodeElement;
NodeElementEnumerator: IEnumVariant;
NodeElements: _UANodeElementCollection;
ReferencesNodeId: _UANodeId;
Client:= TEasyUAClient.create(self);
ReferencesNodeId := CoUANodeId.Create;
ReferencesNodeId.StandardName := 'References';

EndpointDescriptor := CoUAEndpointDescriptor.Create;
EndpointDescriptor.UrlString := 'opc.tcp://';
NodeDescriptor := CoUANodeDescriptor.Create;
NodeDescriptor.NodeId.StandardName := 'Objects';
BrowseParameters := CoUABrowseParameters.Create;
BrowseParameters.NodeClasses := UANodeClass_Object;
NodeElements := Client.BrowseDataNodes(
NodeElementEnumerator := NodeElements.GetEnumerator;
while (NodeElementEnumerator.Next(1, Element, Count) = S_OK) do
NodeElement := IUnknown(Element) as _UANodeElement;
if Assigned(NodeElement) then

I have certificate problem (Check screenshot).

so i have add:

AllowedMessageSecurityModes := UAMessageSecurityModes_SecurityNone;
client.IsolatedParameters.SessionParameters.EndpointSelectionPolicy.AllowZeroSecurityLevel :=TRUE;
Clientconfiguration := TEasyUAClientConfiguration.Create(self);
ClientConfiguration.SharedParameters.EngineParameters.CertificateAcceptancePolicy.AcceptAnyCertificate := true;
ClientConfiguration.SharedParameters.EngineParameters.CertificateAcceptancePolicy.AllowUserAcceptCertificate := true;
// ClientConfiguration.SharedParameters.EngineParameters.CertificateAcceptancePolicy.TrustedEndpointUrlStrings := (ANode.NODE.DataObject as TInfo).EndPoint);

But i have same problem


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