diff --git a/src/addon/messages/pages/contacts/contacts.ts b/src/addon/messages/pages/contacts/contacts.ts
index d27dc3662..047961507 100644
--- a/src/addon/messages/pages/contacts/contacts.ts
+++ b/src/addon/messages/pages/contacts/contacts.ts
@@ -73,6 +73,11 @@ export class AddonMessagesContactsPage implements OnDestroy {
      * User entered the page.
      */
     ionViewDidEnter(): void {
+        if (!this.splitviewCtrl.isOn()) {
+            this.selectedUserId.contacts = null;
+            this.selectedUserId.requests = null;
+        }
+
         this.tabsComponent && this.tabsComponent.ionViewDidEnter();
     }
 
diff --git a/src/addon/mod/lesson/components/index/addon-mod-lesson-index.html b/src/addon/mod/lesson/components/index/addon-mod-lesson-index.html
index e4e86a524..a394f589b 100644
--- a/src/addon/mod/lesson/components/index/addon-mod-lesson-index.html
+++ b/src/addon/mod/lesson/components/index/addon-mod-lesson-index.html
@@ -13,7 +13,7 @@
 <!-- Content. -->
 <core-loading [hideUntil]="loaded" class="core-loading-center">
 
-    <core-tabs [selectedIndex]="selectedTab">
+    <core-tabs [hideUntil]="loaded" [selectedIndex]="selectedTab">
         <!-- Index/Preview tab. -->
         <core-tab [title]="'addon.mod_lesson.preview' | translate">
             <ng-template>
diff --git a/src/addon/mod/lesson/components/index/index.ts b/src/addon/mod/lesson/components/index/index.ts
index 015434ce0..ada4eded7 100644
--- a/src/addon/mod/lesson/components/index/index.ts
+++ b/src/addon/mod/lesson/components/index/index.ts
@@ -535,6 +535,8 @@ export class AddonModLessonIndexComponent extends CoreCourseModuleMainActivityCo
             const preventReason = this.lessonProvider.getPreventAccessReason(this.accessInfo, true);
             if (preventReason) {
                 this.preventMessages = [preventReason];
+            } else {
+                this.preventMessages = [];
             }
 
             // Log view now that we have the password.
diff --git a/src/addon/mod/lesson/providers/lesson.ts b/src/addon/mod/lesson/providers/lesson.ts
index dd15ed778..6af1f19d1 100644
--- a/src/addon/mod/lesson/providers/lesson.ts
+++ b/src/addon/mod/lesson/providers/lesson.ts
@@ -314,10 +314,10 @@ export class AddonModLessonProvider {
      * @param {boolean} [review] If the user wants to review just after finishing (1 hour margin).
      * @param {any} [pageIndex] Object containing all the pages indexed by ID. If not defined, it will be calculated.
      * @param {string} [siteId] Site ID. If not defined, current site.
-     * @return {Promise<{reviewMode: boolean, progress: number, ongoingScore: string}>} Promise resolved with the data.
+     * @return {Promise<{reviewmode: boolean, progress: number, ongoingscore: string}>} Promise resolved with the data.
      */
     protected calculateOfflineData(lesson: any, accessInfo?: any, password?: string, review?: boolean, pageIndex?: any,
-            siteId?: string): Promise<{reviewMode: boolean, progress: number, ongoingScore: string}> {
+            siteId?: string): Promise<{reviewmode: boolean, progress: number, ongoingscore: string}> {
 
         accessInfo = accessInfo || {};
 
@@ -342,9 +342,9 @@ export class AddonModLessonProvider {
 
         return Promise.all(promises).then(() => {
             return {
-                reviewMode: reviewMode,
+                reviewmode: reviewMode,
                 progress: progress,
-                ongoingScore: ongoingMessage
+                ongoingscore: ongoingMessage
             };
         });
     }
diff --git a/src/addon/mod/lesson/providers/report-link-handler.ts b/src/addon/mod/lesson/providers/report-link-handler.ts
index e07c9978c..76d8703ac 100644
--- a/src/addon/mod/lesson/providers/report-link-handler.ts
+++ b/src/addon/mod/lesson/providers/report-link-handler.ts
@@ -105,7 +105,7 @@ export class AddonModLessonReportLinkHandler extends CoreContentLinksHandlerBase
                 module: module,
                 courseId: Number(courseId),
                 action: 'report',
-                group: groupId
+                group: isNaN(groupId) ? null : groupId
             };
 
             this.linkHelper.goInSite(navCtrl, 'AddonModLessonIndexPage', pageParams, siteId);
diff --git a/src/components/tabs/tabs.ts b/src/components/tabs/tabs.ts
index d46d12170..1e38c3cd8 100644
--- a/src/components/tabs/tabs.ts
+++ b/src/components/tabs/tabs.ts
@@ -144,9 +144,7 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges, OnDe
     ionViewDidEnter(): void {
         this.isCurrentView = true;
 
-        if (this.initialized) {
-            this.calculateSlides();
-        }
+        this.calculateSlides();
 
         this.registerBackButtonAction();
     }
@@ -201,6 +199,7 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges, OnDe
         if (this.getIndex(tab) == -1) {
             this.tabs.push(tab);
             this.sortTabs();
+
             this.calculateSlides();
 
             if (this.initialized && this.tabs.length > 1 && this.tabBarHeight == 0) {
@@ -217,7 +216,7 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges, OnDe
      * Calculate slides.
      */
     calculateSlides(): void {
-        if (!this.isCurrentView || !this.tabsShown) {
+        if (!this.isCurrentView || !this.tabsShown || !this.initialized) {
             // Don't calculate if component isn't in current view, the calculations are wrong.
             return;
         }
@@ -301,10 +300,10 @@ export class CoreTabsComponent implements OnInit, AfterViewInit, OnChanges, OnDe
             }
         }
 
+        this.initialized = true;
+
         // Check which arrows should be shown.
         this.calculateSlides();
-
-        this.initialized = true;
     }
 
     /**
diff --git a/src/providers/ws.ts b/src/providers/ws.ts
index 7372bbfff..de16e3103 100644
--- a/src/providers/ws.ts
+++ b/src/providers/ws.ts
@@ -261,7 +261,7 @@ export class CoreWSProvider {
             data = data[0];
 
             if (data.error) {
-                return rejectWithError(data);
+                return rejectWithError(data.exception);
             }
 
             return data.data;