diff --git a/helper/webhooktool.php b/helper/webhooktool.php
index 94458e2..ee8051a 100644
--- a/helper/webhooktool.php
+++ b/helper/webhooktool.php
@@ -5,61 +5,66 @@
  * @author Go Namhyeon <gnh1201@gmail.com>
  * @brief WebhookTools
  * @trademark
- * * `NateOn` is trademark of SK Communications Co Ltd, or SK planet Co Ltd, or other SK internet business
+ * * `NateOn` is trademark of SK Communications Co Ltd., SK Planet Co Ltd., or other SK businesses.
  * * `Discord' is trademark of Discord Inc. (Originally Hammer And Chisel)
  * * `Slack` is trademark of Slack Technologies Inc.
  */
 
+if(check_function_exists("send_web_hook")) {
+	function send_web_hook($message, $networkid, $options=array()) {
+		$response = false;
+		$id = get_value_in_array("id", $options, "");
 
-function send_web_hook($message, $networkid, $options=array()) {
-	$response = false;
-	$id = get_value_in_array("id", $options, "");
+		switch($networkid) {
+			case "nateon":
+				$request_url = sprintf("https://teamroom.nate.com/api/webhook/%s", $id);
+				if(loadHelper("webpagetool")) {
+					$response = get_web_page($request_url, "post", array(
+						"headers" => array(
+							"Content-Type" => "application/x-www-form-urlencoded",
+						),
+						"data" => array(
+							"content" => urlencode($message),
+						),
+					));
+				}
 
-	switch($networkid) {
-		case "nateon":
-			$request_url = sprintf("https://teamroom.nate.com/api/webhook/%s", $id);
-			if(loadHelper("webpagetool")) {
-				$response = get_web_page($request_url, "post", array(
-					"headers" => array(
-						"Content-Type" => "application/x-www-form-urlencoded",
-					),
-					"data" => array(
-						"content" => urlencode($message),
-					),
-				));
-			}
-						
-						
-			break;
 
-		case "discord":
-			$request_url = sprintf("https://discordapp.com/api/webhooks/%s", $id);
-			$response = get_web_json($request_url, "jsondata", array(
-				"headers" => array(
-					"Content-Type" => "application/json",
-				),
-				"data" => array(
-					"content" => $message,
-					"username" => get_value_in_array("username", $options, "anonymous"),
-				),
-			));
-			break;
-			
-		case "slack":
-			$request_url = sprintf("https://hooks.slack.com/services/%s", $id);
-			$response = get_web_json($request_url, "jsondata", array(
-				"headers" => array(
-					"Content-Type" => "application/json",
-				),
-				"data" => array(
-					"channel" => sprintf("#%s", get_value_in_array("channel", $options, "general")),
-					"username" => get_value_in_array("username", $options, "anonymous"),
-					"text" => $message,
-					"icon_emoji" => sprintf(":%s:", get_value_in_array("emoji", $options, "ghost")),
-				),
-			));
-			break;
+				break;
+
+			case "discord":
+				$request_url = sprintf("https://discordapp.com/api/webhooks/%s", $id);
+				if(loadHelper("webpagetool")) {
+					$response = get_web_json($request_url, "jsondata", array(
+						"headers" => array(
+							"Content-Type" => "application/json",
+						),
+						"data" => array(
+							"content" => $message,
+							"username" => get_value_in_array("username", $options, "anonymous"),
+						),
+					));
+				}
+				break;
+
+			case "slack":
+				$request_url = sprintf("https://hooks.slack.com/services/%s", $id);
+				if(loadHelper("webpagetool")) {
+					$response = get_web_json($request_url, "jsondata", array(
+						"headers" => array(
+							"Content-Type" => "application/json",
+						),
+						"data" => array(
+							"channel" => sprintf("#%s", get_value_in_array("channel", $options, "general")),
+							"username" => get_value_in_array("username", $options, "anonymous"),
+							"text" => $message,
+							"icon_emoji" => sprintf(":%s:", get_value_in_array("emoji", $options, "ghost")),
+						),
+					));
+				}
+				break;
+		}
+
+		return $response;
 	}
-
-	return $response;
 }