diff --git a/Options.qml b/Options.qml
index 7d32359..65cd55f 100644
--- a/Options.qml
+++ b/Options.qml
@@ -36,10 +36,10 @@ Pane {
                     hoverEnabled: true
                     ToolTip.visible: hovered
                     ToolTip.text: qsTr("Path to the folder containing the addons")
-                    enabled: Control.status == Control.Ready && addonsReady
+                    enabled: Engine.status == Engine.Ready && addonsReady
                 }
                 Button {
-                    enabled: Control.status == Control.Ready && addonsReady
+                    enabled: Engine.status == Engine.Ready && addonsReady
                     text: qsTr("Browse")
                     onClicked: {fileDialog.selector = index; fileDialog.currentFolder = "file://" + Engine.addonsPaths[index]; fileDialog.visible = true}
                     hoverEnabled: true
diff --git a/addon.cpp b/addon.cpp
index 90b3972..3cda1fa 100644
--- a/addon.cpp
+++ b/addon.cpp
@@ -691,7 +691,7 @@ AutoPtr<git_reference> Addon::branchRef(QString name)
 void Addon::delegate(QString taskname, auto work, auto callback, bool force)
 {
     Q_ASSERT_X(QThread::currentThread() == thread(), "delegate", "Attempt to delegate from another thread.");
-    if (status() != Status::Ready && !force) {
+    if (m_lock && !force) {
         qInfo() << name() << "Enqueueing" << taskname;
         m_tasks.enqueue({taskname, [this, taskname, work, callback](){delegate(taskname, work,callback);}});
         return;
@@ -700,10 +700,12 @@ void Addon::delegate(QString taskname, auto work, auto callback, bool force)
     setProgress(0);
     setTotal(0);
     setStatus(Status::Busy);
+    m_lock = true;
     using ret_t = typename std::invoke_result<decltype(work)>::type;
     QFuture<ret_t> fut = QtConcurrent::run(m_pool, work);
     QFutureWatcher<ret_t> *fw = new QFutureWatcher<ret_t>();
     connect(fw, &QFutureWatcher<ret_t>::finished, [this, callback, fw, taskname](){
+        m_lock = false;
         if (fw->isCanceled()) {
             try {
                 fw->waitForFinished();
@@ -714,7 +716,6 @@ void Addon::delegate(QString taskname, auto work, auto callback, bool force)
             }
             return;
         }
-        setStatus(Status::Ready);
         TaskQueue old;
         m_tasks.swap(old);
 
@@ -725,7 +726,9 @@ void Addon::delegate(QString taskname, auto work, auto callback, bool force)
 
         m_tasks.append(old);
 
-        if (!m_tasks.isEmpty() && status() != Status::Busy)
+        if (m_tasks.empty())
+            setStatus(Status::Ready);
+        else if (!m_lock)
             m_tasks.dequeue().second();
     });
     connect(fw, &QFutureWatcher<ret_t>::finished, fw, &QFutureWatcher<ret_t>::deleteLater);
diff --git a/addon.h b/addon.h
index 6c7a4cd..690031f 100644
--- a/addon.h
+++ b/addon.h
@@ -59,6 +59,8 @@ class Addon : public QObject
     QMutex m_mutex;
     QWaitCondition m_wait;
     void *m_result;
+
+    bool m_lock = false;
 public:
     Q_PROPERTY(QString name READ name WRITE setName NOTIFY nameChanged)
     Q_PROPERTY(QStringList branches READ branches WRITE setBranches NOTIFY branchesChanged)
diff --git a/control.cpp b/control.cpp
index 03b22c7..027ee16 100644
--- a/control.cpp
+++ b/control.cpp
@@ -86,7 +86,7 @@ void Control::removeTocSuffixes(QString &string)
 void Control::delegate(QString taskname, auto work, auto callback)
 {
     Q_ASSERT_X(QThread::currentThread() == thread(), "delegate", "Attempt to delegate from another thread.");
-    if (status() != Status::Ready) {
+    if (m_lock) {
         qInfo() << "Enqueueing" << taskname;
         m_tasks.enqueue({taskname, [this, taskname, work, callback](){delegate(taskname, work,callback);}});
         return;
@@ -95,12 +95,13 @@ void Control::delegate(QString taskname, auto work, auto callback)
     setStatusMessage(taskname);
     setProgress(0);
     setTotal(0);
-    setStatus(Status::Busy);
+    BusyLock lock(this);
+    m_lock = true;
     using ret_t = typename std::invoke_result<decltype(work)>::type;
     QFuture<ret_t> fut = QtConcurrent::run(m_pool, work);
     QFutureWatcher<ret_t> *fw = new QFutureWatcher<ret_t>();
-    connect(fw, &QFutureWatcher<ret_t>::finished, [this, callback, fw](){
-        setStatus(Status::Ready);
+    connect(fw, &QFutureWatcher<ret_t>::finished, [this, callback, fw, lock=std::move(lock)](){
+        m_lock = false;
         TaskQueue old;
         m_tasks.swap(old);
 
@@ -111,7 +112,9 @@ void Control::delegate(QString taskname, auto work, auto callback)
 
         m_tasks.append(old);
 
-        if (!m_tasks.isEmpty() && status() != Status::Busy)
+        if (m_tasks.empty())
+            setStatus(Status::Ready);
+        else if (!m_lock)
             m_tasks.dequeue().second();
     });
     connect(fw, &QFutureWatcher<ret_t>::finished, fw, &QFutureWatcher<ret_t>::deleteLater);
@@ -340,6 +343,7 @@ void Control::saveAddonsPaths()
 void Control::scanForAddons(int i)
 {
     if (i == -1) {
+        BusyLock lock(this);
         foreach (Addon *addon, m_addons)
             addon->deleteLater();
         QList<Addon *> ol;
@@ -703,3 +707,25 @@ bool Control::selfUpdates() const
     return false;
 #endif
 }
+
+int Control::BusyLock::count = 0;
+
+Control::BusyLock::BusyLock(Control *c)
+{
+    m_locked = c;
+    m_locked->setStatus(Status::Busy);
+    count++;
+}
+
+Control::BusyLock::BusyLock(BusyLock &&other)
+{
+    m_locked = other.m_locked;
+    other.m_locked = nullptr;
+}
+
+Control::BusyLock::~BusyLock()
+{
+    if (m_locked)
+        if (!--count && m_locked->m_tasks.empty())
+            m_locked->setStatus(Status::Ready);
+}
diff --git a/control.h b/control.h
index aa050f3..f23688b 100644
--- a/control.h
+++ b/control.h
@@ -45,14 +45,26 @@ public:
 
 int check_git_return(int code);
 
+
 class Control : public QObject
 {
+
+    class BusyLock
+    {
+        static int count;
+        Control* m_locked = nullptr;
+    public:
+        BusyLock(Control* c);
+        BusyLock(BusyLock&& other);
+        ~BusyLock();
+    };
     Q_OBJECT
 
     using TaskQueue = QQueue<QPair<QString,std::function<void()>>>;
     TaskQueue m_tasks;
 
     QList<Addon *> m_addons;
+    bool m_lock = false;
 
 public:
     Q_PROPERTY(QString version READ version CONSTANT)
diff --git a/main.qml b/main.qml
index 487195c..7684c20 100644
--- a/main.qml
+++ b/main.qml
@@ -30,7 +30,7 @@ ApplicationWindow {
     property bool addonsReady: false
     Component.onCompleted: {
         availableUpdates = Qt.binding(function(){
-            if (!addonsReady)
+            if (!(Engine.status == Engine.Ready && addonsReady))
                 return -1;
             var count = 0
             for (var i = 0; i < Engine.addons.length; i++) {
@@ -40,16 +40,18 @@ ApplicationWindow {
             }
             return count
         })
-        addonsReady = Qt.binding(function(){
-            for (var i = 0; i < Engine.addons.length; i++) {
-                var addon = Engine.addons[i]
-                if (addon.status == Addon.Status.Busy)
-                    return false
-            }
-            return true
-        })
+        addonsReady = Qt.binding(checkAddonsReady)
     }
 
+    function checkAddonsReady(){
+        for (var i = 0; i < Engine.addons.length; i++) {
+            var addon = Engine.addons[i]
+            console.debug(addon.status)
+            if (addon.status == Addon.Status.Busy)
+                return false
+        }
+        return true
+    }
     function updateAll() {
         for (var i = 0; i < Engine.addons.length; i++) {
             var addon = Engine.addons[i]
@@ -59,6 +61,8 @@ ApplicationWindow {
     }
 
     onAvailableUpdatesChanged: {
+        if (availableUpdates == -1)
+            return;
         if (availableUpdates > 0) {
             tray.showMessage("Addons updates available", "You have " + availableUpdates + " addons waiting for update.", 1, 5000)
         } else {
@@ -81,7 +85,7 @@ ApplicationWindow {
         icon.name: "view-refresh"
         onTriggered: Engine.scanForAddons()
         shortcut: StandardKey.Refresh
-        enabled: Control.status == Control.Ready && addonsReady
+        enabled: Engine.status == Engine.Ready && addonsReady
     }
     Action {
         id: addAction
@@ -94,7 +98,7 @@ ApplicationWindow {
         icon.name: "export-symbolic"
         onTriggered: exportListDialog.visible = true
 
-        enabled: Control.status == Control.Ready && addonsReady
+        enabled: Engine.status == Engine.Ready && addonsReady
         shortcut: StandardKey.SaveAs
     }
     Action {