diff --git a/UI/Templates/PreferencesUI/UIxPreferences.wox b/UI/Templates/PreferencesUI/UIxPreferences.wox
index 435914f906..0e84e8cf62 100644
--- a/UI/Templates/PreferencesUI/UIxPreferences.wox
+++ b/UI/Templates/PreferencesUI/UIxPreferences.wox
@@ -818,6 +818,7 @@
                   ng-model="app.preferences.defaults.Vacation.enabled"
                   ng-true-value="1"
                   ng-false-value="0"
+                  ng-change="app.updateVacationDates()"
                   label:aria-label="Enable vacation auto reply">
                 <var:string label:value="Enable vacation auto reply"/>
               </md-checkbox>
@@ -894,16 +895,16 @@
                       ng-model="app.preferences.defaults.Vacation.startDateEnabled"
                       ng-true-value="1"
                       ng-false-value="0"
-                      ng-change="app.updateVacationDates()">
+                      ng-change="app.toggleVacationStartDate()">
                     <var:string label:value="Enable auto reply on" />
                   </md-checkbox>
                   <md-input-container>
                     <md-datepicker
-                      ng-disabled="app.preferences.defaults.Vacation.startDateEnabled == 0"
-                      ng-model="app.preferences.defaults.Vacation.startDate"
-                      ng-change="app.updateVacationDates()"
-                      md-min-date="app.vacationStartDateMin"
-                      md-max-date="app.vacationEndDate"><!-- datepicker --></md-datepicker>
+                        name="vacationStartDate"
+                        ng-disabled="!app.preferences.defaults.Vacation.startDateEnabled"
+                        ng-model="app.preferences.defaults.Vacation.startDate"
+                        md-date-filter="app.validateVacationStartDate"
+                        sg-reset-on-disabled="sg-reset-on-disabled"><!-- datepicker --></md-datepicker>
                   </md-input-container>
                 </div>
 
@@ -912,15 +913,16 @@
                       ng-model="app.preferences.defaults.Vacation.endDateEnabled"
                       ng-true-value="1"
                       ng-false-value="0"
-                      ng-change="app.updateVacationDates()">
+                      ng-change="app.toggleVacationEndDate()">
                     <var:string label:value="Disable auto reply on" />
                   </md-checkbox>
                   <md-input-container>
-                  <md-datepicker
-                      ng-disabled="app.preferences.defaults.Vacation.endDateEnabled == 0"
-                      ng-model="app.preferences.defaults.Vacation.endDate"
-                      ng-change="app.updateVacationDates()"
-                      md-min-date="app.vacationStartDate"><!-- datepicker --></md-datepicker>
+                    <md-datepicker
+                        name="vacationEndDate"
+                        ng-disabled="!app.preferences.defaults.Vacation.endDateEnabled"
+                        ng-model="app.preferences.defaults.Vacation.endDate"
+                        md-date-filter="app.validateVacationEndDate"
+                        sg-reset-on-disabled="sg-reset-on-disabled"><!-- datepicker --></md-datepicker>
                   </md-input-container>
                 </div>
 
diff --git a/UI/WebServerResources/js/Common/sgResetOnDisabled.directive.js b/UI/WebServerResources/js/Common/sgResetOnDisabled.directive.js
new file mode 100644
index 0000000000..8ba6d43438
--- /dev/null
+++ b/UI/WebServerResources/js/Common/sgResetOnDisabled.directive.js
@@ -0,0 +1,50 @@
+/* -*- Mode: javascript; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+
+(function() {
+  'use strict';
+
+  /**
+   * sgResetOnDisabled - A directive to reset any error of a datepicker when marked
+   *                     as disabled.
+   * @memberof SOGo.Common
+   * @ngInject
+   * @example:
+
+   <md-datepicker
+     ng-model="myDate"
+     ng-disabled="!myDateEnabled"
+     sg-reset-on-disabled>
+  */
+  function sgResetOnDisabled() {
+    return {
+      link: postLink,
+      require: 'mdDatepicker',
+      restrict: 'A'
+    };
+
+    function postLink(scope, element, attrs, datepickerCtrl) {
+      function getInput() {
+        return element.find('input').eq(0);
+      }
+
+      // We need to wait for the datepicker directive to be compiled
+      var listener = scope.$watch(getInput, function (input) {
+        var ngModel;
+
+        if (input.length) {
+          listener(); // self release
+          datepickerCtrl.$scope.$watch('ctrl.isDisabled', function(isDisabled) {
+            if (isDisabled)
+              if (datepickerCtrl.ngModelCtrl.$invalid)
+                // Trigger the event that will reset the errors and the model value
+                datepickerCtrl.$scope.$emit('md-calendar-change', datepickerCtrl.date);
+          });
+        }
+      });
+    }
+  }
+
+  angular
+    .module('SOGo.Common')
+    .directive('sgResetOnDisabled', sgResetOnDisabled);
+})();
diff --git a/UI/WebServerResources/js/Preferences/PreferencesController.js b/UI/WebServerResources/js/Preferences/PreferencesController.js
index f23b11fff7..71b716fbe0 100644
--- a/UI/WebServerResources/js/Preferences/PreferencesController.js
+++ b/UI/WebServerResources/js/Preferences/PreferencesController.js
@@ -9,7 +9,7 @@
    */
   PreferencesController.$inject = ['$q', '$window', '$state', '$mdMedia', '$mdSidenav', '$mdDialog', '$mdToast', 'sgFocus', 'Dialog', 'User', 'Account', 'statePreferences', 'Authentication'];
   function PreferencesController($q, $window, $state, $mdMedia, $mdSidenav, $mdDialog, $mdToast, focus, Dialog, User, Account, statePreferences, Authentication) {
-    var vm = this, account, mailboxes = [], today = new Date(), tomorrow = today.addDays(1);
+    var vm = this, account, mailboxes = [], today = new Date(), tomorrow = today.beginOfDay().addDays(1);
 
     vm.preferences = statePreferences;
     vm.passwords = { newPassword: null, newPasswordConfirmation: null };
@@ -39,6 +39,11 @@
     vm.timeZonesSearchText = '';
     vm.sieveVariablesCapability = ($window.sieveCapabilities.indexOf('variables') >= 0);
     vm.updateVacationDates = updateVacationDates;
+    vm.toggleVacationStartDate = toggleVacationStartDate;
+    vm.toggleVacationEndDate = toggleVacationEndDate;
+    vm.validateVacationStartDate = validateVacationStartDate;
+    vm.validateVacationEndDate = validateVacationEndDate;
+
 
     // Fetch a flatten version of the mailboxes list of the main account (0)
     // This list will be forwarded to the Sieve filter controller
@@ -370,32 +375,78 @@
     }
 
     function updateVacationDates() {
-      if (statePreferences.defaults &&
-          statePreferences.defaults.Vacation &&
-          statePreferences.defaults.Vacation.enabled) {
-
-        // Determine minimum dates
-        vm.vacationStartDateMin = undefined;
-        if (statePreferences.defaults.Vacation.startDateEnabled) {
-          vm.vacationStartDateMin = tomorrow;
-          vm.vacationStartDate = statePreferences.defaults.Vacation.startDate;
+      var d = vm.preferences.defaults;
+
+      if (d &&
+          d.Vacation &&
+          d.Vacation.enabled) {
+        toggleVacationStartDate();
+        toggleVacationEndDate();
+      }
+    }
+
+    function toggleVacationStartDate() {
+      var v;
+
+      v = vm.preferences.defaults.Vacation;
+
+      if (v.startDateEnabled) {
+        // Enabling the start date
+        if (v.endDateEnabled && v.startDate.getTime() > v.endDate.getTime()) {
+          v.startDate = new Date(v.endDate.getTime());
+          v.startDate.addDays(-1);
+        }
+        if (v.startDate.getTime() < tomorrow.getTime()) {
+          v.startDate = new Date(tomorrow.getTime());
+        }
+      }
+    }
+
+    function toggleVacationEndDate() {
+      var v;
+
+      v = vm.preferences.defaults.Vacation;
+
+      if (v.endDateEnabled) {
+        // Enabling the end date
+        if (v.startDateEnabled && v.endDate.getTime() < v.startDate.getTime()) {
+          v.endDate = new Date(v.startDate.getTime());
+          v.endDate.addDays(1);
+        }
+        else if (v.endDate.getTime() < tomorrow.getTime()) {
+          v.endDate = new Date(tomorrow.getTime());
+        }
+      }
+    }
+
+    function validateVacationStartDate(date) {
+      var d = vm.preferences.defaults, r = true;
+      if (d &&
+          d.Vacation &&
+          d.Vacation.enabled) {
+        if (d.Vacation.startDateEnabled) {
+          r = (!d.Vacation.endDateEnabled ||
+               date.getTime() < d.Vacation.endDate.getTime()) &&
+            date.getTime() >= tomorrow.getTime();
         }
-        else if (statePreferences.defaults.Vacation.endDateEnabled)
-          vm.vacationStartDate = tomorrow;
-        else
-          vm.vacationStartDate = undefined;
-
-        // Determine maximum value of start date
-        if (statePreferences.defaults.Vacation.endDateEnabled)
-          vm.vacationEndDate = statePreferences.defaults.Vacation.endDate;
-        else
-          vm.vacationEndDate = undefined;
       }
-      else {
-        vm.vacationStartDateMin = undefined;
-        vm.vacationStartDate = undefined;
-        vm.vacationEndDate = undefined;
+
+      return r;
+    }
+
+    function validateVacationEndDate(date) {
+      var d = vm.preferences.defaults, r = true;
+      if (d &&
+          d.Vacation &&
+          d.Vacation.enabled) {
+        if (d.Vacation.endDateEnabled) {
+          r = (!d.Vacation.startDateEnabled ||
+               date.getTime() > d.Vacation.startDate.getTime()) &&
+            date.getTime() >= tomorrow.getTime();
+        }
       }
+
+      return r;
     }
   }