diff --git a/src-ui/logics/_useBackendErrorHandling.js b/src-ui/logics/_useBackendErrorHandling.js
index c9d99e50..d5987a1b 100644
--- a/src-ui/logics/_useBackendErrorHandling.js
+++ b/src-ui/logics/_useBackendErrorHandling.js
@@ -16,6 +16,7 @@ import {
     useDeepLAuthKey,
 
     useOscIpAddress,
+    useWebsocket,
 } from "@logics_configs";
 import { ui_configs } from "../ui_configs";
 
@@ -31,106 +32,144 @@ export const _useBackendErrorHandling = () => {
     const { updateSpeakerPhraseTimeout } = useSpeakerPhraseTimeout();
     const { updateSpeakerMaxWords } = useSpeakerMaxWords();
 
-    const { updateDeepLAuthKey, saveErrorDeepLAuthKey } = useDeepLAuthKey();
+    const { updateDeepLAuthKey } = useDeepLAuthKey();
 
     const { updateOscIpAddress } = useOscIpAddress();
+    const { updateEnableWebsocket, updateWebsocketHost, updateWebsocketPort } = useWebsocket();
 
-    const errorHandling_Backend = ({message, data, endpoint, _result}) => {
-        switch (message) {
-            case "No mic device detected":
-                showNotification_Error(t("common_error.no_device_mic"));
-                break;
-            case "No speaker device detected":
-                showNotification_Error(t("common_error.no_device_speaker"));
-                break;
+    const errorHandling_Backend = ({message, data, endpoint, result}) => {
+        switch (endpoint) {
+            case "/run/error_device":
+                if (message === "No mic device detected") showNotification_Error(t("common_error.no_device_mic"));
+                if (message === "No speaker device detected") showNotification_Error(t("common_error.no_device_speaker"));
+                return;
 
-            case "Mic energy threshold value is out of range":
-                showNotification_Error(t("common_error.threshold_invalid_value",
-                    { min: ui_configs.mic_threshold_min, max: ui_configs.mic_threshold_max },
-                ));
-                break;
-            case "Speaker energy threshold value is out of range":
-                showNotification_Error(t("common_error.threshold_invalid_value",
-                    { min: ui_configs.speaker_threshold_min, max: ui_configs.speaker_threshold_max },
-                ));
-                break;
+            case "/set/data/mic_threshold":
+                if (message === "Mic energy threshold value is out of range") {
+                    showNotification_Error(t("common_error.threshold_invalid_value",
+                        { min: ui_configs.mic_threshold_min, max: ui_configs.mic_threshold_max },
+                    ));
+                };
+                return;
+            case "/set/data/speaker_threshold":
+                if (message === "Speaker energy threshold value is out of range") {
+                    showNotification_Error(t("common_error.threshold_invalid_value",
+                        { min: ui_configs.speaker_threshold_min, max: ui_configs.speaker_threshold_max },
+                    ));
+                }
+                return;
 
-            case "CTranslate2 weight download error":
-                showNotification_Error(t("common_error.failed_download_weight_ctranslate2"));
-                break;
-            case "Whisper weight download error":
-                showNotification_Error(t("common_error.failed_download_weight_whisper"));
-                break;
+            case "/run/error_ctranslate2_weight":
+                if (message === "CTranslate2 weight download error") showNotification_Error(t("common_error.failed_download_weight_ctranslate2"));
+                return;
+            case "/run/error_whisper_weight":
+                if (message === "Whisper weight download error") showNotification_Error(t("common_error.failed_download_weight_whisper"));
+                return;
 
-            case "Translation engine limit error":
-                showNotification_Error(t("common_error.translation_limit"));
-                break;
+            case "/run/error_translation_engine":
+                if (message === "Translation engine limit error") showNotification_Error(t("common_error.translation_limit"));
+                return;
 
-            case "DeepL auth key length is not correct":
-                updateDeepLAuthKey(data);
-                showNotification_Error(t("common_error.deepl_auth_key_invalid_length"));
-                break;
-            case "Authentication failure of deepL auth key":
-                updateDeepLAuthKey(data);
-                showNotification_Error(t("common_error.deepl_auth_key_failed_authentication"));
-                break;
+            case "/set/data/deepl_auth_key":
+                if (message === "DeepL auth key length is not correct") {
+                    updateDeepLAuthKey(data);
+                    showNotification_Error(t("common_error.deepl_auth_key_invalid_length"));
+                } else if (message === "Authentication failure of deepL auth key") {
+                    updateDeepLAuthKey(data);
+                    showNotification_Error(t("common_error.deepl_auth_key_failed_authentication"));
+                } else { // Exception
+                    updateDeepLAuthKey(data);
+                    showNotification_Error(message);
+                }
+                return;
 
-            case "Mic record timeout value is out of range":
-                updateMicRecordTimeout(data);
-                showNotification_Error(
-                    t("common_error.invalid_value_mic_record_timeout",
-                    { mic_phrase_timeout_label: t("config_page.transcription.mic_phrase_timeout.label") }
-                ));
-                break;
-            case "Mic phrase timeout value is out of range":
-                updateMicPhraseTimeout(data);
-                showNotification_Error(
-                    t("common_error.invalid_value_mic_phrase_timeout",
-                    { mic_record_timeout_label: t("config_page.transcription.mic_record_timeout.label") }
-                ));
-                break;
-            case "Mic max phrases value is out of range":
-                updateMicMaxWords(data);
-                showNotification_Error(t("common_error.invalid_value_mic_max_phrase"));
-                break;
+            case "/set/data/mic_record_timeout":
+                if (message === "Mic record timeout value is out of range") {
+                    updateMicRecordTimeout(data);
+                    showNotification_Error(t("common_error.invalid_value_mic_record_timeout", {
+                        mic_phrase_timeout_label: t("config_page.transcription.mic_phrase_timeout.label")
+                    }));
+                }
+                return;
+            case "/set/data/mic_phrase_timeout":
+                if (message === "Mic phrase timeout value is out of range") {
+                    updateMicPhraseTimeout(data);
+                    showNotification_Error(t("common_error.invalid_value_mic_phrase_timeout", {
+                        mic_record_timeout_label: t("config_page.transcription.mic_record_timeout.label")
+                    }));
+                }
+                return;
+            case "/set/data/mic_max_phrases":
+                if (message === "Mic max phrases value is out of range") {
+                    updateMicMaxWords(data);
+                    showNotification_Error(t("common_error.invalid_value_mic_max_phrase"));
+                }
+                return;
 
 
-            case "Speaker record timeout value is out of range":
-                updateSpeakerRecordTimeout(data);
-                showNotification_Error(
-                    t("common_error.invalid_value_speaker_record_timeout",
-                    { speaker_phrase_timeout_label: t("config_page.transcription.speaker_phrase_timeout.label") }
-                ));
-                break;
-            case "Speaker phrase timeout value is out of range":
-                updateSpeakerPhraseTimeout(data);
-                showNotification_Error(
-                    t("common_error.invalid_value_speaker_phrase_timeout",
-                    { speaker_record_timeout_label: t("config_page.transcription.speaker_record_timeout.label") }
-                ));
-                break;
-            case "Speaker max phrases value is out of range":
-                updateSpeakerMaxWords(data);
-                showNotification_Error(t("common_error.invalid_value_speaker_max_phrase"));
-                break;
+            case "/set/data/speaker_record_timeout":
+                if (message === "Speaker record timeout value is out of range") {
+                    updateSpeakerRecordTimeout(data);
+                    showNotification_Error(t("common_error.invalid_value_speaker_record_timeout", {
+                        speaker_phrase_timeout_label: t("config_page.transcription.speaker_phrase_timeout.label")
+                    }));
+                }
+                return;
+            case "/set/data/speaker_phrase_timeout":
+                if (message === "Speaker phrase timeout value is out of range") {
+                    updateSpeakerPhraseTimeout(data);
+                    showNotification_Error(t("common_error.invalid_value_speaker_phrase_timeout", {
+                        speaker_record_timeout_label: t("config_page.transcription.speaker_record_timeout.label")
+                    }));
+                }
+                return;
+            case "/set/data/speaker_max_phrases":
+                if (message === "Speaker max phrases value is out of range") {
+                    updateSpeakerMaxWords(data);
+                    showNotification_Error(t("common_error.invalid_value_speaker_max_phrase"));
+                }
+                return;
 
 
             // Advanced Settings, error messages are set by Backend (EN only)
-            case "Invalid IP address":
-                updateOscIpAddress(data);
-                showNotification_Error(message);
-                break;
+            case "/set/data/osc_ip_address":
+                if (message === "Invalid IP address") {
+                    updateOscIpAddress(data);
+                    showNotification_Error(message);
+                } else if (message === "Cannot set IP address") {
+                    updateOscIpAddress(data);
+                    showNotification_Error(message);
+                } // else? (Backend will send the message "Cannot set IP address" when throw Exception)
+                return;
 
-            case "Cannot set IP address":
-                updateOscIpAddress(data);
-                showNotification_Error(message);
-                break;
+
+            case "/set/enable/websocket_server":
+                if (message === "WebSocket server host or port is not available") {
+                    updateEnableWebsocket(data);
+                    showNotification_Error(message);
+                }
+                return;
+
+            case "/set/data/websocket_host":
+                if (message === "Invalid IP address") {
+                    updateWebsocketHost(data);
+                    showNotification_Error(message);
+                } else if (message === "WebSocket server host is not available") {
+                    updateWebsocketHost(data);
+                    showNotification_Error(message);
+                }
+                return;
+
+            case "/set/data/websocket_port":
+                if (message === "WebSocket server port is not available") {
+                    updateWebsocketPort(data);
+                    showNotification_Error(message);
+                }
+                return;
 
             default:
-                // determine by endpoint, not message.
-                if (endpoint === "/set/data/deepl_auth_key") saveErrorDeepLAuthKey({message, data, endpoint, _result});
-
-                break;
+                console.error(`Invalid endpoint or message: ${endpoint}\nmessage: ${message}\nresult: ${JSON.stringify(result)}`);
+                return;
         }
 
     }
diff --git a/src-ui/logics/configs/translation/useDeepLAuthKey.js b/src-ui/logics/configs/translation/useDeepLAuthKey.js
index f93fdd4f..a568dfe9 100644
--- a/src-ui/logics/configs/translation/useDeepLAuthKey.js
+++ b/src-ui/logics/configs/translation/useDeepLAuthKey.js
@@ -29,11 +29,6 @@ export const useDeepLAuthKey = () => {
         showNotification_Success(t("config_page.translation.deepl_auth_key.auth_key_success"));
     };
 
-    const saveErrorDeepLAuthKey = ({data, message}) => {
-        updateDeepLAuthKey(data);
-        showNotification_Error(message);
-    };
-
     return {
         currentDeepLAuthKey,
         getDeepLAuthKey,
@@ -41,7 +36,6 @@ export const useDeepLAuthKey = () => {
         setDeepLAuthKey,
         deleteDeepLAuthKey,
 
-        saveErrorDeepLAuthKey,
         savedDeepLAuthKey,
     };
 };
\ No newline at end of file
diff --git a/src-ui/logics/useReceiveRoutes.js b/src-ui/logics/useReceiveRoutes.js
index 1d89be33..3cde999a 100644
--- a/src-ui/logics/useReceiveRoutes.js
+++ b/src-ui/logics/useReceiveRoutes.js
@@ -530,30 +530,6 @@ export const useReceiveRoutes = () => {
         "/get/data/transcription_engines": ()=>{}, // Not implemented on UI yet. (if ai_models has not been detected, this will be blank array[]. if the ai_models are ok but just network has not connected, it'l be only ["Whisper"])
     };
 
-    const error_status_routes = {
-        "/run/error_device": errorHandling_Backend,
-
-        "/run/error_ctranslate2_weight": errorHandling_Backend,
-        "/run/error_whisper_weight": errorHandling_Backend,
-
-        "/set/data/deepl_auth_key": errorHandling_Backend,
-
-        "/run/error_translation_engine": errorHandling_Backend,
-
-        "/set/data/mic_threshold": errorHandling_Backend,
-        "/set/data/mic_record_timeout": errorHandling_Backend,
-        "/set/data/mic_phrase_timeout": errorHandling_Backend,
-        "/set/data/mic_max_phrases": errorHandling_Backend,
-
-        "/set/data/speaker_threshold": errorHandling_Backend,
-        "/set/data/speaker_record_timeout": errorHandling_Backend,
-        "/set/data/speaker_phrase_timeout": errorHandling_Backend,
-        "/set/data/speaker_max_phrases": errorHandling_Backend,
-
-        "/set/data/osc_ip_address": errorHandling_Backend,
-    };
-
-
     const receiveRoutes = (parsed_data) => {
         const initDataSyncProcess = (payload) => {
             for (const [endpoint, value] of Object.entries(payload)) {
@@ -583,17 +559,12 @@ export const useReceiveRoutes = () => {
                 break;
 
             case 400:
-                const error_route = error_status_routes[parsed_data.endpoint];
-                if (error_route) {
-                    error_route({
-                        message: parsed_data.result.message,
-                        data: parsed_data.result.data,
-                        endpoint: parsed_data.endpoint,
-                        _result: parsed_data.result,
-                    });
-                } else {
-                    handleInvalidEndpoint(parsed_data);
-                }
+                errorHandling_Backend({
+                    message: parsed_data.result.message,
+                    data: parsed_data.result.data,
+                    endpoint: parsed_data.endpoint,
+                    result: parsed_data.result,
+                });
                 break;
             case 500:
                 showNotification_Error(