diff --git a/electron-projects/ucap-webmessenger-electron/src/index.ts b/electron-projects/ucap-webmessenger-electron/src/index.ts
index 6765a305..01183491 100644
--- a/electron-projects/ucap-webmessenger-electron/src/index.ts
+++ b/electron-projects/ucap-webmessenger-electron/src/index.ts
@@ -445,8 +445,6 @@ ipcMain.on(
     const downloadPath = args[0] as string;
 
     if (!!downloadPath && downloadPath.length > 0) {
-      console.log('in electron', downloadPath);
-
       appStorage.downloadPath = downloadPath;
       log.info('downloadPath is changed to ', appStorage.downloadPath);
 
diff --git a/projects/ucap-webmessenger-app/src/app/guards/auto-login.guard.ts b/projects/ucap-webmessenger-app/src/app/guards/auto-login.guard.ts
index bd099cd9..bc462712 100644
--- a/projects/ucap-webmessenger-app/src/app/guards/auto-login.guard.ts
+++ b/projects/ucap-webmessenger-app/src/app/guards/auto-login.guard.ts
@@ -16,6 +16,7 @@ import {
 import { AppUserInfo, KEY_APP_USER_INFO } from '@app/types/app-user-info.type';
 import { environment } from '../../environments/environment';
 import * as AuthenticationStore from '@app/store/account/authentication';
+import { KEY_LOGOUT_INFO, LogoutInfo } from '@app/types';
 
 @Injectable({
   providedIn: 'root'
@@ -42,14 +43,14 @@ export class AppAutoLoginGuard implements CanActivate {
         environment.customConfig.appKey
       );
 
-      const personLogout: boolean = this.sessionStorageService.get(
-        'PERSON_LOGOUT'
+      const personLogout: LogoutInfo = this.sessionStorageService.get(
+        KEY_LOGOUT_INFO
       );
 
       if (
         !!appUserInfo &&
         appUserInfo.settings.general.autoLogin &&
-        !personLogout
+        !personLogout.personLogout
       ) {
         this.store.dispatch(
           AuthenticationStore.webLogin({
diff --git a/projects/ucap-webmessenger-app/src/app/layouts/messenger/components/messages.component.ts b/projects/ucap-webmessenger-app/src/app/layouts/messenger/components/messages.component.ts
index 5ffa719e..2a704c77 100644
--- a/projects/ucap-webmessenger-app/src/app/layouts/messenger/components/messages.component.ts
+++ b/projects/ucap-webmessenger-app/src/app/layouts/messenger/components/messages.component.ts
@@ -857,7 +857,6 @@ export class MessagesComponent implements OnInit, OnDestroy, AfterViewInit {
       this.nativeService
         .selectSaveFilePath(value.fileInfo.fileName)
         .then(result => {
-          console.log(result);
           if (!!result && result.length > 0) {
             this.saveFile(value, result);
           } else {
diff --git a/projects/ucap-webmessenger-app/src/app/layouts/messenger/dialogs/profile/profile.dialog.component.ts b/projects/ucap-webmessenger-app/src/app/layouts/messenger/dialogs/profile/profile.dialog.component.ts
index 6a05e426..a3d4740b 100644
--- a/projects/ucap-webmessenger-app/src/app/layouts/messenger/dialogs/profile/profile.dialog.component.ts
+++ b/projects/ucap-webmessenger-app/src/app/layouts/messenger/dialogs/profile/profile.dialog.component.ts
@@ -104,8 +104,6 @@ export class ProfileDialogComponent implements OnInit, OnDestroy {
 
     this.editableProfileImage =
       environment.productConfig.CommonSetting.editableProfileImage;
-
-    console.log(data.openProfileOptions);
   }
 
   ngOnInit() {
diff --git a/projects/ucap-webmessenger-app/src/app/pages/account/components/login.page.component.ts b/projects/ucap-webmessenger-app/src/app/pages/account/components/login.page.component.ts
index cf60a6fa..681f25b0 100644
--- a/projects/ucap-webmessenger-app/src/app/pages/account/components/login.page.component.ts
+++ b/projects/ucap-webmessenger-app/src/app/pages/account/components/login.page.component.ts
@@ -3,6 +3,7 @@ import { Component, OnInit, OnDestroy } from '@angular/core';
 import { Store, select } from '@ngrx/store';
 
 import { Company } from '@ucap-webmessenger/api-external';
+import { ServerErrorCode } from '@ucap-webmessenger/protocol';
 
 import * as AppStore from '@app/store';
 import * as AuthenticationStore from '@app/store/account/authentication';
@@ -24,8 +25,12 @@ import {
 } from '@app/layouts/messenger/dialogs/account/notice.dialog.component';
 
 import { environment } from '../../../../environments/environment';
-import { LocalStorageService } from '@ucap-webmessenger/web-storage';
+import {
+  LocalStorageService,
+  SessionStorageService
+} from '@ucap-webmessenger/web-storage';
 import { AppUserInfo, KEY_APP_USER_INFO } from '@app/types/app-user-info.type';
+import { LogoutInfo, KEY_LOGOUT_INFO } from '@app/types';
 
 @Component({
   selector: 'app-page-account-login',
@@ -79,7 +84,8 @@ export class LoginPageComponent implements OnInit, OnDestroy {
     private store: Store<any>,
     private router: Router,
     private dialogService: DialogService,
-    private localStorageService: LocalStorageService
+    private localStorageService: LocalStorageService,
+    private sessionStorageService: SessionStorageService
   ) {
     this.useRememberMe =
       environment.productConfig.authentication.rememberMe.use;
@@ -163,7 +169,33 @@ export class LoginPageComponent implements OnInit, OnDestroy {
     this.customInitilize();
   }
 
-  customInitilize() {
+  async customInitilize() {
+    const personLogout: LogoutInfo = this.sessionStorageService.get(
+      KEY_LOGOUT_INFO
+    );
+
+    if (
+      !!personLogout &&
+      !!personLogout.reasonCode &&
+      personLogout.reasonCode === ServerErrorCode.ERRCD_DUPLICATE
+    ) {
+      const result = await this.dialogService.open<
+        AlertDialogComponent,
+        AlertDialogData,
+        AlertDialogResult
+      >(AlertDialogComponent, {
+        width: '360px',
+        data: {
+          title: '',
+          html: `다른 디바이스에서 로그인하였습니다.<br/> * Ip : ${personLogout.ip}<br/> * Mac : ${personLogout.mac}`
+        }
+      });
+
+      this.sessionStorageService.set<LogoutInfo>(KEY_LOGOUT_INFO, {
+        personLogout: true
+      } as LogoutInfo);
+    }
+
     // Daesang..
     this.fixedCompany = environment.companyConfig.fixedCompanyCode;
     this.fixedNotiBtnText = '이용 주의사항';
diff --git a/projects/ucap-webmessenger-app/src/app/pages/messenger/components/main.page.component.ts b/projects/ucap-webmessenger-app/src/app/pages/messenger/components/main.page.component.ts
index 59fe0492..5f4f9d1b 100644
--- a/projects/ucap-webmessenger-app/src/app/pages/messenger/components/main.page.component.ts
+++ b/projects/ucap-webmessenger-app/src/app/pages/messenger/components/main.page.component.ts
@@ -307,7 +307,7 @@ export class MainPageComponent implements OnInit, OnDestroy {
           .pipe(
             take(1),
             map(res => {
-              console.log(res);
+              this.logger.debug(res);
             }),
             catchError(error => of(this.logger.debug(error)))
           )
diff --git a/projects/ucap-webmessenger-app/src/app/services/authentication.service.ts b/projects/ucap-webmessenger-app/src/app/services/authentication.service.ts
index c3a93584..ebd1d012 100644
--- a/projects/ucap-webmessenger-app/src/app/services/authentication.service.ts
+++ b/projects/ucap-webmessenger-app/src/app/services/authentication.service.ts
@@ -10,7 +10,9 @@ import {
   KEY_LOGIN_INFO,
   KEY_LOGIN_RES_INFO,
   KEY_VER_INFO,
-  KEY_URL_INFO
+  KEY_URL_INFO,
+  KEY_LOGOUT_INFO,
+  LogoutInfo
 } from '../types';
 import { PasswordUtil } from '@ucap-webmessenger/pi';
 
@@ -96,7 +98,7 @@ export class AppAuthenticationService {
       environment.customConfig.appKey
     );
 
-    this.sessionStorageService.remove('PERSON_LOGOUT');
+    this.sessionStorageService.remove(KEY_LOGOUT_INFO);
   }
 
   logout() {
@@ -104,7 +106,5 @@ export class AppAuthenticationService {
     this.sessionStorageService.remove(KEY_VER_INFO);
     this.sessionStorageService.remove(KEY_LOGIN_INFO);
     this.sessionStorageService.remove(KEY_URL_INFO);
-
-    this.sessionStorageService.set<boolean>('PERSON_LOGOUT', true);
   }
 }
diff --git a/projects/ucap-webmessenger-app/src/app/services/notification.service.ts b/projects/ucap-webmessenger-app/src/app/services/notification.service.ts
index 6bfc401e..4d0a4963 100644
--- a/projects/ucap-webmessenger-app/src/app/services/notification.service.ts
+++ b/projects/ucap-webmessenger-app/src/app/services/notification.service.ts
@@ -10,7 +10,8 @@ import {
   SSVC_TYPE_LOGOUT_REMOTE_NOTI,
   AuthenticationProtocolService,
   LogoutResponse,
-  LogoutRemoteNotification
+  LogoutRemoteNotification,
+  LogoutNotification
 } from '@ucap-webmessenger/protocol-authentication';
 
 import { NGXLogger } from 'ngx-logger';
@@ -97,13 +98,17 @@ import {
   SSVC_TYPE_UMG_NOTI,
   UmgNotiNotification
 } from '@ucap-webmessenger/protocol-umg';
-import { LocalStorageService } from '@ucap-webmessenger/web-storage';
+import {
+  LocalStorageService,
+  SessionStorageService
+} from '@ucap-webmessenger/web-storage';
 import { AppUserInfo, KEY_APP_USER_INFO } from '@app/types/app-user-info.type';
 
 import { environment } from '../../environments/environment';
 import { NotificationMethod } from '@ucap-webmessenger/core';
 import { Dictionary } from '@ngrx/entity';
 import { MessageType } from '@ucap-webmessenger/api-message';
+import { LogoutInfo, KEY_LOGOUT_INFO } from '@app/types';
 
 @Injectable()
 export class AppNotificationService {
@@ -117,6 +122,7 @@ export class AppNotificationService {
     private statusProtocolService: StatusProtocolService,
     private umgProtocolService: UmgProtocolService,
     private localStorageService: LocalStorageService,
+    private sessionStorageService: SessionStorageService,
     @Inject(UCAP_NATIVE_SERVICE) private nativeService: NativeService,
     private store: Store<any>,
     private logger: NGXLogger
@@ -129,11 +135,18 @@ export class AppNotificationService {
           switch (notiOrRes.SSVC_TYPE) {
             case SSVC_TYPE_LOGOUT_RES:
               {
-                const res = notiOrRes as LogoutResponse;
+                const res = notiOrRes as LogoutNotification;
                 this.logger.debug(
                   'Notification::authenticationProtocolService::LogoutResponse',
                   res
                 );
+
+                this.sessionStorageService.set<LogoutInfo>(KEY_LOGOUT_INFO, {
+                  personLogout: true,
+                  reasonCode: res.reasonCode,
+                  ip: res.ip,
+                  mac: res.mac
+                } as LogoutInfo);
               }
               break;
             case SSVC_TYPE_LOGOUT_REMOTE_NOTI:
diff --git a/projects/ucap-webmessenger-app/src/app/store/account/authentication/effects.ts b/projects/ucap-webmessenger-app/src/app/store/account/authentication/effects.ts
index 18bf25cf..6f4e3641 100644
--- a/projects/ucap-webmessenger-app/src/app/store/account/authentication/effects.ts
+++ b/projects/ucap-webmessenger-app/src/app/store/account/authentication/effects.ts
@@ -48,7 +48,9 @@ import {
   KEY_LOGIN_INFO,
   EnvironmentsInfo,
   KEY_ENVIRONMENTS_INFO,
-  KEY_URL_INFO
+  KEY_URL_INFO,
+  LogoutInfo,
+  KEY_LOGOUT_INFO
 } from '@app/types';
 import { AppAuthenticationService } from '@app/services/authentication.service';
 import { NGXLogger } from 'ngx-logger';
@@ -174,6 +176,10 @@ export class Effects {
         switchMap(action => {
           return this.authenticationProtocolService.logout({}).pipe(
             map(res => {
+              this.sessionStorageService.set<LogoutInfo>(KEY_LOGOUT_INFO, {
+                personLogout: true
+              } as LogoutInfo);
+
               this.store.dispatch(loginRedirect());
             }),
             catchError(error => of(error))
diff --git a/projects/ucap-webmessenger-app/src/app/types/index.ts b/projects/ucap-webmessenger-app/src/app/types/index.ts
index 4d21b5e1..44ba29af 100644
--- a/projects/ucap-webmessenger-app/src/app/types/index.ts
+++ b/projects/ucap-webmessenger-app/src/app/types/index.ts
@@ -1,5 +1,6 @@
 export * from './environment.type';
 export * from './login-info.type';
+export * from './logout-info.type';
 export * from './userselect.dialog.type';
 export * from './right-drawer.type';
 export * from './sticker-info.type';
diff --git a/projects/ucap-webmessenger-app/src/app/types/logout-info.type.ts b/projects/ucap-webmessenger-app/src/app/types/logout-info.type.ts
new file mode 100644
index 00000000..b07b1575
--- /dev/null
+++ b/projects/ucap-webmessenger-app/src/app/types/logout-info.type.ts
@@ -0,0 +1,8 @@
+export const KEY_LOGOUT_INFO = 'ucap::LOGOUT_INFO';
+
+export interface LogoutInfo {
+  personLogout: boolean;
+  reasonCode?: number;
+  ip?: string;
+  mac?: string;
+}
diff --git a/projects/ucap-webmessenger-native-browser/src/lib/services/browser-native.service.ts b/projects/ucap-webmessenger-native-browser/src/lib/services/browser-native.service.ts
index 1f4abbae..18235515 100644
--- a/projects/ucap-webmessenger-native-browser/src/lib/services/browser-native.service.ts
+++ b/projects/ucap-webmessenger-native-browser/src/lib/services/browser-native.service.ts
@@ -74,7 +74,7 @@ export class BrowserNativeService extends NativeService {
 
   getNetworkInfo(): Promise<any> {
     return new Promise<any>((resolve, reject) => {
-      resolve(null);
+      resolve([{ ip: 'Browser', mac: 'browser' }]);
     });
   }
 
diff --git a/projects/ucap-webmessenger-protocol-authentication/src/lib/protocols/logout.ts b/projects/ucap-webmessenger-protocol-authentication/src/lib/protocols/logout.ts
index d18d2ab8..87de30c6 100644
--- a/projects/ucap-webmessenger-protocol-authentication/src/lib/protocols/logout.ts
+++ b/projects/ucap-webmessenger-protocol-authentication/src/lib/protocols/logout.ts
@@ -5,7 +5,8 @@ import {
   ProtocolDecoder,
   ProtocolMessage,
   PacketBody,
-  decodeProtocolMessage
+  decodeProtocolMessage,
+  ProtocolNotification
 } from '@ucap-webmessenger/protocol';
 
 // tslint:disable-next-line: no-empty-interface
@@ -15,6 +16,12 @@ export interface LogoutResponse extends ProtocolResponse {
   reasonCode?: number;
 }
 
+export interface LogoutNotification extends ProtocolNotification {
+  reasonCode?: number;
+  ip?: string;
+  mac?: string;
+}
+
 export const encodeLogout: ProtocolEncoder<LogoutRequest> = (
   req: LogoutRequest
 ) => {
@@ -27,6 +34,16 @@ export const decodeLogout: ProtocolDecoder<LogoutResponse> = (
   message: ProtocolMessage
 ) => {
   return decodeProtocolMessage(message, {
-    reasonCode: message.bodyList[0]
+    reasonCode: Number(message.bodyList[0])
   } as LogoutResponse);
 };
+
+export const decodeLogoutNotification: ProtocolDecoder<LogoutNotification> = (
+  message: ProtocolMessage
+) => {
+  return decodeProtocolMessage(message, {
+    reasonCode: Number(message.bodyList[0]),
+    ip: !!message.bodyList[1] ? message.bodyList[1] : '',
+    mac: !!message.bodyList[2] ? message.bodyList[2] : ''
+  } as LogoutNotification);
+};
diff --git a/projects/ucap-webmessenger-protocol-authentication/src/lib/services/authentication-protocol.service.ts b/projects/ucap-webmessenger-protocol-authentication/src/lib/services/authentication-protocol.service.ts
index 8ec7a9c8..368d5034 100644
--- a/projects/ucap-webmessenger-protocol-authentication/src/lib/services/authentication-protocol.service.ts
+++ b/projects/ucap-webmessenger-protocol-authentication/src/lib/services/authentication-protocol.service.ts
@@ -23,7 +23,8 @@ import {
   LogoutRequest,
   LogoutResponse,
   encodeLogout,
-  decodeLogout
+  decodeLogout,
+  decodeLogoutNotification
 } from '../protocols/logout';
 import {
   encodeLogoutRemote,
@@ -56,7 +57,9 @@ export class AuthenticationProtocolService {
           switch (message.subServiceType) {
             case SSVC_TYPE_LOGOUT_RES:
               {
-                this.logoutNotificationSubject.next(decodeLogout(message));
+                this.logoutNotificationSubject.next(
+                  decodeLogoutNotification(message)
+                );
               }
               break;
             case SSVC_TYPE_LOGOUT_REMOTE_NOTI:
diff --git a/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/sound-viewer.component.ts b/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/sound-viewer.component.ts
index e4a053c3..b870c7dc 100644
--- a/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/sound-viewer.component.ts
+++ b/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/sound-viewer.component.ts
@@ -61,7 +61,6 @@ export class SoundViewerComponent implements OnInit {
   }
 
   onChangeTimeSlider(e: MatSliderChange): void {
-    console.log('onChangeTimeSlider', e.value);
     this.audioPlayer.nativeElement.currentTime = e.value;
   }
 
diff --git a/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/video-viewer.component.ts b/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/video-viewer.component.ts
index f0ab6894..de03c16e 100644
--- a/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/video-viewer.component.ts
+++ b/projects/ucap-webmessenger-ui/src/lib/components/file-viewer/video-viewer.component.ts
@@ -61,7 +61,6 @@ export class VideoViewerComponent implements OnInit {
   }
 
   onChangeTimeSlider(e: MatSliderChange): void {
-    console.log('onChangeTimeSlider', e.value);
     this.audioPlayer.nativeElement.currentTime = e.value;
   }
 
diff --git a/projects/ucap-webmessenger-ui/src/lib/data-source/virtual-scroll-tree-flat.data-source.ts b/projects/ucap-webmessenger-ui/src/lib/data-source/virtual-scroll-tree-flat.data-source.ts
index 1987f671..d3a40ac0 100644
--- a/projects/ucap-webmessenger-ui/src/lib/data-source/virtual-scroll-tree-flat.data-source.ts
+++ b/projects/ucap-webmessenger-ui/src/lib/data-source/virtual-scroll-tree-flat.data-source.ts
@@ -115,7 +115,6 @@ export class VirtualScrollTreeFlatDataSource<T, F> extends DataSource<F> {
   }
 
   disconnect() {
-    console.log('VirtualScrollTreeFlatDataSource disconnect');
     if (!!this.connectSubject) {
       this.connectSubject.next();
       this.connectSubject.unsubscribe();