# OpcNotificationFailedEventArgs Members

> Reference: Provides the event data for the NotificationFailed and NotificationFailed events.

<dl class="api-definition">
<dt>Type</dt>
<dd><a href="./">OpcNotificationFailedEventArgs</a></dd>
<dt>Namespace</dt>
<dd><a href="../namespaces/opc.uafx.client">Opc.UaFx.Client</a></dd>
<dt>Assembly</dt>
<dd>Opc.UaFx.Advanced.dll</dd>
<dt>Package</dt>
<dd>Opc.UaFx.Advanced v2.59.0</dd>
<dt>Also in</dt>
<dd>Opc.UaFx.Client</dd>
</dl>

Inherits members from [EventArgs](https://learn.microsoft.com/dotnet/api/system.eventargs).

## Properties

### Exception

Gets the exception which describes why the notification message failed to be received.

<div class="api-signature" data-lang="csharp">

```csharp
public OpcException Exception { get; }
```

</div>

<div class="api-signature" data-lang="vbnet">

```vbnet
Public ReadOnly Property Exception As OpcException
```

</div>

**Property value**

[OpcException](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcexception/)

An instance of the [OpcException](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcexception/) class whose [Code](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcexception/members#code) states the reason, for example [BadEncodingLimitsExceeded](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcstatuscode/#badencodinglimitsexceeded) or [BadDecodingError](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcstatuscode/#baddecodingerror) if a value of the message cannot be decoded, or [BadMessageNotAvailable](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcstatuscode/#badmessagenotavailable) if the server no longer holds the message and its notifications are lost.

### Handled

Gets or sets a value indicating whether the event handler has completely handled the event or whether the system should continue its own processing.

<div class="api-signature" data-lang="csharp">

```csharp
public bool Handled { get; set; }
```

</div>

<div class="api-signature" data-lang="vbnet">

```vbnet
Public Property Handled As Boolean
```

</div>

**Property value**

[Boolean](https://learn.microsoft.com/dotnet/api/system.boolean)

The value true if the event has been completely handled; otherwise, the value false. The default value is false.

### Subscription

Gets the [OpcSubscription](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.client.opcsubscription/) the notification message belongs to.

<div class="api-signature" data-lang="csharp">

```csharp
public OpcSubscription Subscription { get; }
```

</div>

<div class="api-signature" data-lang="vbnet">

```vbnet
Public ReadOnly Property Subscription As OpcSubscription
```

</div>

**Property value**

[OpcSubscription](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.client.opcsubscription/)

An instance of the [OpcSubscription](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.client.opcsubscription/) class, or a null reference (Nothing in Visual Basic) if it is not known. A response which cannot be processed does not state the subscription of its message; it is known once the message is requested again from the server and fails again.