diff --git a/apps/common/locale.js b/apps/common/locale.js
index bcd4270ba..abed04e94 100644
--- a/apps/common/locale.js
+++ b/apps/common/locale.js
@@ -84,7 +84,11 @@ Common.Locale = new(function() {
     };
 
     var _getCurrentLanguage = function() {
-        return (currentLang || defLang);
+        return currentLang;
+    };
+
+    var _getLoadedLanguage = function() {
+        return loadedLang;
     };
 
     var _getUrlParameterByName = function(name) {
@@ -109,9 +113,12 @@ Common.Locale = new(function() {
                 }
                 return response.json();
             }).then(function(response) {
-                if ( response.json )
+                if ( response.json ) {
+                    if (!response.ok)
+                        throw new Error('server error');
+
                     return response.json();
-                else {
+                } else {
                     l10n = response;
                     /* to break promises chain */
                     throw new Error('loaded');
@@ -123,8 +130,10 @@ Common.Locale = new(function() {
                 l10n = l10n || {};
                 apply && _applyLocalization();
                 if ( e.message == 'loaded' ) {
-                } else
+                } else {
+                    currentLang = null;
                     console.log('fetch error: ' + e);
+                }
             });
     };
 
diff --git a/apps/common/main/lib/component/Window.js b/apps/common/main/lib/component/Window.js
index 661424bc2..95edd58b9 100644
--- a/apps/common/main/lib/component/Window.js
+++ b/apps/common/main/lib/component/Window.js
@@ -632,7 +632,7 @@ define([
 
                 this.$window = $('#' + this.initConfig.id);
 
-                if (Common.Locale.getCurrentLanguage() !== 'en')
+                if (Common.Locale.getCurrentLanguage() && Common.Locale.getCurrentLanguage() !== 'en')
                     this.$window.attr('applang', Common.Locale.getCurrentLanguage());
 
                 this.binding.keydown = _.bind(_keydown,this);
diff --git a/apps/documenteditor/main/app/controller/Main.js b/apps/documenteditor/main/app/controller/Main.js
index 183a3194a..b74fd5b0e 100644
--- a/apps/documenteditor/main/app/controller/Main.js
+++ b/apps/documenteditor/main/app/controller/Main.js
@@ -1250,7 +1250,7 @@ define([
                 if (Asc.c_oLicenseResult.ExpiredLimited === licType)
                     this._state.licenseType = licType;
 
-                if ( this.onServerVersion(params.asc_getBuildVersion()) ) return;
+                if ( this.onServerVersion(params.asc_getBuildVersion()) || !this.onLanguageLoaded()) return;
 
                 this.permissions.review = (this.permissions.review === undefined) ? (this.permissions.edit !== false) : this.permissions.review;
 
@@ -2476,6 +2476,18 @@ define([
                 this._renameDialog.show(Common.Utils.innerWidth() - this._renameDialog.options.width - 15, 30);
             },
 
+            onLanguageLoaded: function() {
+                if (!Common.Locale.getCurrentLanguage()) {
+                    Common.UI.warning({
+                        msg: this.errorLang,
+                        callback: function() {
+                        }
+                    });
+                    return false;
+                }
+                return true;
+            },
+
             leavePageText: 'You have unsaved changes in this document. Click \'Stay on this Page\' then \'Save\' to save them. Click \'Leave this Page\' to discard all the unsaved changes.',
             criticalErrorTitle: 'Error',
             notcriticalErrorTitle: 'Warning',
@@ -2844,7 +2856,8 @@ define([
             txtNoTableOfFigures: "No table of figures entries found.",
             txtTableOfFigures: 'Table of figures',
             txtStyle_endnote_text: 'Endnote Text',
-            txtTOCHeading: 'TOC Heading'
+            txtTOCHeading: 'TOC Heading',
+            errorLang: 'The interface language is not loaded.<br>Please contact your Document Server administrator.'
         }
     })(), DE.Controllers.Main || {}))
 });
\ No newline at end of file
diff --git a/apps/documenteditor/mobile/app/controller/Main.js b/apps/documenteditor/mobile/app/controller/Main.js
index 66f8d59fc..9f6c281d5 100644
--- a/apps/documenteditor/mobile/app/controller/Main.js
+++ b/apps/documenteditor/mobile/app/controller/Main.js
@@ -783,7 +783,7 @@ define([
                 if (Asc.c_oLicenseResult.ExpiredLimited === licType)
                     me._state.licenseType = licType;
 
-                if ( me.onServerVersion(params.asc_getBuildVersion()) ) return;
+                if ( me.onServerVersion(params.asc_getBuildVersion()) || !me.onLanguageLoaded()) return;
 
                 me.appOptions.permissionsLicense = licType;
                 me.permissions.review         = (me.permissions.review === undefined) ? (me.permissions.edit !== false) : me.permissions.review;
@@ -1497,6 +1497,17 @@ define([
                 }
             },
 
+            onLanguageLoaded: function() {
+                if (!Common.Locale.getCurrentLanguage()) {
+                    uiApp.alert(
+                        this.errorLang,
+                        this.notcriticalErrorTitle
+                    );
+                    return false;
+                }
+                return true;
+            },
+
             leavePageText: 'You have unsaved changes in this document. Click \'Stay on this Page\' to await the autosave of the document. Click \'Leave this Page\' to discard all the unsaved changes.',
             criticalErrorTitle: 'Error',
             notcriticalErrorTitle: 'Warning',
@@ -1643,7 +1654,8 @@ define([
             txtEvenPage: "Even Page",
             txtOddPage: "Odd Page",
             txtSameAsPrev: "Same as Previous",
-            txtCurrentDocument: "Current Document"
+            txtCurrentDocument: "Current Document",
+            errorLang: 'The interface language is not loaded.<br>Please contact your Document Server administrator.'
         }
     })(), DE.Controllers.Main || {}))
 });
\ No newline at end of file
diff --git a/apps/presentationeditor/main/app/controller/Main.js b/apps/presentationeditor/main/app/controller/Main.js
index c2fcc6337..764938ed8 100644
--- a/apps/presentationeditor/main/app/controller/Main.js
+++ b/apps/presentationeditor/main/app/controller/Main.js
@@ -976,7 +976,7 @@ define([
                 if (Asc.c_oLicenseResult.ExpiredLimited === licType)
                     this._state.licenseType = licType;
 
-                if ( this.onServerVersion(params.asc_getBuildVersion()) ) return;
+                if ( this.onServerVersion(params.asc_getBuildVersion()) || !this.onLanguageLoaded() ) return;
 
                 if (params.asc_getRights() !== Asc.c_oRights.Edit)
                     this.permissions.edit = false;
@@ -2107,6 +2107,18 @@ define([
                 this._renameDialog.show(Common.Utils.innerWidth() - this._renameDialog.options.width - 15, 30);
             },
 
+            onLanguageLoaded: function() {
+                if (!Common.Locale.getCurrentLanguage()) {
+                    Common.UI.warning({
+                        msg: this.errorLang,
+                        callback: function() {
+                        }
+                    });
+                    return false;
+                }
+                return true;
+            },
+
             // Translation
             leavePageText: 'You have unsaved changes in this document. Click \'Stay on this Page\' then \'Save\' to save them. Click \'Leave this Page\' to discard all the unsaved changes.',
             criticalErrorTitle: 'Error',
@@ -2469,7 +2481,8 @@ define([
             textRenameLabel: 'Enter a name to be used for collaboration',
             textRenameError: 'User name must not be empty.',
             textLongName: 'Enter a name that is less than 128 characters.',
-            textGuest: 'Guest'
+            textGuest: 'Guest',
+            errorLang: 'The interface language is not loaded.<br>Please contact your Document Server administrator.'
         }
     })(), PE.Controllers.Main || {}))
 });
diff --git a/apps/presentationeditor/mobile/app/controller/Main.js b/apps/presentationeditor/mobile/app/controller/Main.js
index 4c9c14894..2c66e159b 100644
--- a/apps/presentationeditor/mobile/app/controller/Main.js
+++ b/apps/presentationeditor/mobile/app/controller/Main.js
@@ -715,7 +715,7 @@ define([
                 if (Asc.c_oLicenseResult.ExpiredLimited === licType)
                     me._state.licenseType = licType;
 
-                if ( me.onServerVersion(params.asc_getBuildVersion()) ) return;
+                if ( me.onServerVersion(params.asc_getBuildVersion()) || !me.onLanguageLoaded() ) return;
 
                 me.appOptions.permissionsLicense = licType;
                 me.permissions.review         = (me.permissions.review === undefined) ? (me.permissions.edit !== false) : me.permissions.review;
@@ -1398,6 +1398,17 @@ define([
                 }
             },
 
+            onLanguageLoaded: function() {
+                if (!Common.Locale.getCurrentLanguage()) {
+                    uiApp.alert(
+                        this.errorLang,
+                        this.notcriticalErrorTitle
+                    );
+                    return false;
+                }
+                return true;
+            },
+            
             // Translation
             leavePageText: 'You have unsaved changes in this document. Click \'Stay on this Page\' to await the autosave of the document. Click \'Leave this Page\' to discard all the unsaved changes.',
             criticalErrorTitle: 'Error',
@@ -1573,7 +1584,8 @@ define([
             warnLicenseLimitedRenewed: 'License needs to be renewed.<br>You have a limited access to document editing functionality.<br>Please contact your administrator to get full access',
             warnLicenseLimitedNoAccess: 'License expired.<br>You have no access to document editing functionality.<br>Please contact your administrator.',
             textGuest: 'Guest',
-            txtAddFirstSlide: 'Click to add first slide'
+            txtAddFirstSlide: 'Click to add first slide',
+            errorLang: 'The interface language is not loaded.<br>Please contact your Document Server administrator.'
         }
     })(), PE.Controllers.Main || {}))
 });
\ No newline at end of file
diff --git a/apps/spreadsheeteditor/main/app/controller/Main.js b/apps/spreadsheeteditor/main/app/controller/Main.js
index d674000e4..3e34f052c 100644
--- a/apps/spreadsheeteditor/main/app/controller/Main.js
+++ b/apps/spreadsheeteditor/main/app/controller/Main.js
@@ -1049,7 +1049,7 @@ define([
                     if (Asc.c_oLicenseResult.ExpiredLimited === licType)
                         this._state.licenseType = licType;
 
-                    if ( this.onServerVersion(params.asc_getBuildVersion()) ) return;
+                    if ( this.onServerVersion(params.asc_getBuildVersion()) || !this.onLanguageLoaded() ) return;
 
                     if (params.asc_getRights() !== Asc.c_oRights.Edit)
                         this.permissions.edit = false;
@@ -2452,6 +2452,18 @@ define([
                 this._renameDialog.show(Common.Utils.innerWidth() - this._renameDialog.options.width - 15, 30);
             },
 
+            onLanguageLoaded: function() {
+                if (!Common.Locale.getCurrentLanguage()) {
+                    Common.UI.warning({
+                        msg: this.errorLang,
+                        callback: function() {
+                        }
+                    });
+                    return false;
+                }
+                return true;
+            },
+
             leavePageText: 'You have unsaved changes in this document. Click \'Stay on this Page\' then \'Save\' to save them. Click \'Leave this Page\' to discard all the unsaved changes.',
             criticalErrorTitle: 'Error',
             notcriticalErrorTitle: 'Warning',
@@ -2849,7 +2861,8 @@ define([
             errorPasteMultiSelect: 'This action cannot be done on a multiple range selection.<br>Select a single range and try again.',
             errorPivotWithoutUnderlying: 'The Pivot Table report was saved without the underlying data.<br>Use the \'Refresh\' button to update the report.',
             txtQuarter: 'Qtr',
-            txtOr: '%1 or %2'
+            txtOr: '%1 or %2',
+            errorLang: 'The interface language is not loaded.<br>Please contact your Document Server administrator.'
         }
     })(), SSE.Controllers.Main || {}))
 });
diff --git a/apps/spreadsheeteditor/mobile/app/controller/Main.js b/apps/spreadsheeteditor/mobile/app/controller/Main.js
index 07f75cbf8..e73df8db7 100644
--- a/apps/spreadsheeteditor/mobile/app/controller/Main.js
+++ b/apps/spreadsheeteditor/mobile/app/controller/Main.js
@@ -741,7 +741,7 @@ define([
                     if (Asc.c_oLicenseResult.ExpiredLimited === licType)
                         me._state.licenseType = licType;
 
-                    if ( me.onServerVersion(params.asc_getBuildVersion()) ) return;
+                    if ( me.onServerVersion(params.asc_getBuildVersion()) || !me.onLanguageLoaded() ) return;
 
                     if (params.asc_getRights() !== Asc.c_oRights.Edit) {
                         me.permissions.edit = false;
@@ -1601,6 +1601,17 @@ define([
                 }
             },
 
+            onLanguageLoaded: function() {
+                if (!Common.Locale.getCurrentLanguage()) {
+                    uiApp.alert(
+                        this.errorLang,
+                        this.notcriticalErrorTitle
+                    );
+                    return false;
+                }
+                return true;
+            },
+            
             leavePageText: 'You have unsaved changes in this document. Click \'Stay on this Page\' to await the autosave of the document. Click \'Leave this Page\' to discard all the unsaved changes.',
             criticalErrorTitle: 'Error',
             notcriticalErrorTitle: 'Warning',
@@ -1795,7 +1806,8 @@ define([
             warnLicenseLimitedNoAccess: 'License expired.<br>You have no access to document editing functionality.<br>Please contact your administrator.',
             textGuest: 'Guest',
             errorDataValidate: 'The value you entered is not valid.<br>A user has restricted values that can be entered into this cell.',
-            errorLockedCellPivot: 'You cannot change data inside a pivot table.'
+            errorLockedCellPivot: 'You cannot change data inside a pivot table.',
+            errorLang: 'The interface language is not loaded.<br>Please contact your Document Server administrator.'
         }
     })(), SSE.Controllers.Main || {}))
 });
\ No newline at end of file