Fix device explorer call.

Author: robinsh

articles/iot-hub/iot-hub-devguide-security.md

@@ -273,7 +273,7 @@ The result, which grants access to all functionality for device1, would be:
 `SharedAccessSignature sr=myhub.azure-devices.net%2fdevices%2fdevice1&sig=13y8ejUk2z7PLmvtwR5RqlGBOVwiq7rQR3WZ5xZX3N4%3D&se=1456971697`
 
 > [!NOTE]
-> It's possible to generate a SAS token with the [device explorer](https://github.com/Azure/azure-iot-sdk-csharp/blob/master/tools/DeviceExplorer) tool, the CLI extension command [az iot hub generate-sas-token](/cli/azure/ext/azure-cli-iot-ext/iot/hub?view=azure-cli-latest#ext-azure-cli-iot-ext-az-iot-hub-generate-sas-token), or the [Azure IoT Tools for Visual Studio Code](https://marketplace.visualstudio.com/items?itemName=vsciot-vscode.azure-iot-tools).
+> It's possible to generate a SAS token with the CLI extension command [az iot hub generate-sas-token](/cli/azure/ext/azure-cli-iot-ext/iot/hub?view=azure-cli-latest#ext-azure-cli-iot-ext-az-iot-hub-generate-sas-token), or the [Azure IoT Tools for Visual Studio Code](https://marketplace.visualstudio.com/items?itemName=vsciot-vscode.azure-iot-tools).
 
 ### Use a shared access policy