diff --git a/src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI/Commands/HistoryReadCommand.cs b/src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI/Commands/HistoryReadCommand.cs
index a07dbc1a..b19e20fb 100644
--- a/src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI/Commands/HistoryReadCommand.cs
+++ b/src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI/Commands/HistoryReadCommand.cs
@@ -183,9 +183,10 @@ public class HistoryReadCommand : CommandBase
             await console.Output.WriteLineAsync();
             await console.Output.WriteLineAsync($"{values.Count} values returned.");
         }
-        catch (ServiceResultException ex)
+        catch (ServiceResultException ex) when (ex.InnerException is null)
         {
             // e.g. HistoryReadStatus.ThrowIfRefused: a refusal is an operator-facing outcome, not a crash.
+            // A wrapped failure (certificate validation, identity rejection on connect) keeps its full detail.
             throw new CommandException(ex.Message);
         }
         finally
diff --git a/src/Client/ZB.MOM.WW.OtOpcUa.Client.Shared/Adapters/DefaultEndpointDiscovery.cs b/src/Client/ZB.MOM.WW.OtOpcUa.Client.Shared/Adapters/DefaultEndpointDiscovery.cs
index 9ced2a15..c16c020e 100644
--- a/src/Client/ZB.MOM.WW.OtOpcUa.Client.Shared/Adapters/DefaultEndpointDiscovery.cs
+++ b/src/Client/ZB.MOM.WW.OtOpcUa.Client.Shared/Adapters/DefaultEndpointDiscovery.cs
@@ -92,13 +92,15 @@ internal static class EndpointSelector
         // Only when the scheme matches: a different scheme (https vs opc.tcp) is a different transport.
         var serverUri = new Uri(best.EndpointUrl);
         var requestedUri = new Uri(endpointUrl);
+        // A URL typed without a port (opc.tcp has no registered default, so Port is -1) keeps the advertised port.
+        var port = requestedUri.Port > 0 ? requestedUri.Port : serverUri.Port;
         if (string.Equals(serverUri.Scheme, requestedUri.Scheme, StringComparison.OrdinalIgnoreCase)
-            && (serverUri.Host != requestedUri.Host || serverUri.Port != requestedUri.Port))
+            && (serverUri.Host != requestedUri.Host || serverUri.Port != port))
         {
-            var builder = new UriBuilder(best.EndpointUrl) { Host = requestedUri.Host, Port = requestedUri.Port };
+            var builder = new UriBuilder(best.EndpointUrl) { Host = requestedUri.Host, Port = port };
             best.EndpointUrl = builder.ToString();
             Logger.Debug("Rewrote endpoint from {ServerHost}:{ServerPort} to {RequestedHost}:{RequestedPort}",
-                serverUri.Host, serverUri.Port, requestedUri.Host, requestedUri.Port);
+                serverUri.Host, serverUri.Port, requestedUri.Host, port);
         }
 
         return best;
diff --git a/tests/Client/ZB.MOM.WW.OtOpcUa.Client.Shared.Tests/Adapters/EndpointSelectorTests.cs b/tests/Client/ZB.MOM.WW.OtOpcUa.Client.Shared.Tests/Adapters/EndpointSelectorTests.cs
index 5ebc0e46..ba917d82 100644
--- a/tests/Client/ZB.MOM.WW.OtOpcUa.Client.Shared.Tests/Adapters/EndpointSelectorTests.cs
+++ b/tests/Client/ZB.MOM.WW.OtOpcUa.Client.Shared.Tests/Adapters/EndpointSelectorTests.cs
@@ -197,4 +197,30 @@ public class EndpointSelectorTests
 
         best.EndpointUrl.ShouldBe("opc.tcp://server:4840");
     }
+
+    /// <summary>A URL typed without a port keeps the advertised port (opc.tcp has no default; Uri.Port is -1).</summary>
+    [Fact]
+    public void SelectBest_KeepsAdvertisedPort_WhenRequestedUrlHasNoPort()
+    {
+        var endpoints = new[] { Ep(MessageSecurityMode.None, SecurityPolicies.None, "opc.tcp://internal-host:4840/OtOpcUa") };
+
+        var best = EndpointSelector.SelectBest(endpoints, "opc.tcp://localhost", MessageSecurityMode.None);
+
+        var uri = new Uri(best.EndpointUrl);
+        uri.Host.ShouldBe("localhost");
+        uri.Port.ShouldBe(4840);
+    }
+
+    /// <summary>An IPv6 host is rewritten with its brackets intact.</summary>
+    [Fact]
+    public void SelectBest_RewritesIpv6Host()
+    {
+        var endpoints = new[] { Ep(MessageSecurityMode.None, SecurityPolicies.None, "opc.tcp://internal-host:4840/OtOpcUa") };
+
+        var best = EndpointSelector.SelectBest(endpoints, "opc.tcp://[::1]:4841", MessageSecurityMode.None);
+
+        var uri = new Uri(best.EndpointUrl);
+        uri.Host.ShouldBe("[::1]");
+        uri.Port.ShouldBe(4841);
+    }
 }