diff --git a/src/kiwixapp.cpp b/src/kiwixapp.cpp
index 46f07c7..568b7d5 100644
--- a/src/kiwixapp.cpp
+++ b/src/kiwixapp.cpp
@@ -99,13 +99,17 @@ void KiwixApp::init()
         }
     });
     connect(&m_watcher, &QFileSystemWatcher::directoryChanged, this, [=](QString monitorDir) {
-        m_library.asyncLoadMonitorDir(monitorDir);
+        m_library.asyncUpdateFromDir(monitorDir);
     });
     QString monitorDir = m_settingsManager.getMonitorDir();
-    if (monitorDir != "") {
-        m_library.setMonitorDirZims(m_library.getLibraryZimsFromDir(monitorDir));
-        m_watcher.addPath(monitorDir);
-        m_library.asyncLoadMonitorDir(monitorDir);
+    QString downloadDir = m_settingsManager.getDownloadDir();
+    auto dirList = QSet<QString>({monitorDir, downloadDir});
+    for (auto dir : dirList) {
+        if (dir != "") {
+            m_library.setMonitorDirZims(dir, m_library.getLibraryZimsFromDir(dir));
+            m_watcher.addPath(dir);
+            m_library.asyncUpdateFromDir(dir);
+        }
     }
 }
 
@@ -284,13 +288,14 @@ bool KiwixApp::isCurrentArticleBookmarked()
 
 void KiwixApp::setMonitorDir(const QString &dir) {
     m_settingsManager.setMonitorDir(dir);
-    m_library.setMonitorDirZims(QStringList());
+    m_library.setMonitorDirZims(dir, QStringList());
     for (auto path : m_watcher.directories()) {
         m_watcher.removePath(path);
     }
     if (dir != "") {
         m_watcher.addPath(dir);
-        m_library.asyncLoadMonitorDir(dir);
+        m_watcher.addPath(m_settingsManager.getDownloadDir());
+        m_library.asyncUpdateFromDir(dir);
     }
 }
 
diff --git a/src/library.cpp b/src/library.cpp
index 7d8d371..7ec7318 100644
--- a/src/library.cpp
+++ b/src/library.cpp
@@ -115,9 +115,9 @@ void Library::save()
     m_library.writeBookmarksToFile(kiwix::appendToDirectory(m_libraryDirectory.toStdString(), "library.bookmarks.xml"));
 }
 
-void Library::setMonitorDirZims(QStringList zimList)
+void Library::setMonitorDirZims(QString monitorDir, QStringList zimList)
 {
-    m_monitorDirZims = zimList;
+    m_knownZimsInDir[monitorDir] = zimList;
 }
 
 QStringList Library::getLibraryZimsFromDir(QString dir) const
@@ -133,13 +133,12 @@ QStringList Library::getLibraryZimsFromDir(QString dir) const
     return zimsInDir;
 }
 
-void Library::loadMonitorDir(QString monitorDir)
+void Library::updateFromDir(QString monitorDir)
 {
-    QMutex mutex;
-    QMutexLocker locker(&mutex);
+    QMutexLocker locker(&m_updateFromDirMutex);
     const QDir dir(monitorDir);
     QStringList newDirEntries = dir.entryList({"*.zim"});
-    QStringList oldDirEntries = m_monitorDirZims;
+    QStringList oldDirEntries = m_knownZimsInDir[monitorDir];
     for (auto &str : newDirEntries) {
         str = QDir::toNativeSeparators(monitorDir + "/" + str);
     }
@@ -160,18 +159,20 @@ void Library::loadMonitorDir(QString monitorDir)
         needsRefresh |= manager.addBookFromPath(book.toStdString());
     }
     for (auto bookPath : removedZims) {
-        removeBookFromLibraryById(QString::fromStdString(m_library.getBookByPath(bookPath.toStdString()).getId()));
+        try {
+            removeBookFromLibraryById(QString::fromStdString(m_library.getBookByPath(bookPath.toStdString()).getId()));
+        } catch (...) {}
     }
     if (needsRefresh) {
-        setMonitorDirZims(newDir.values());
         emit(booksChanged());
+        setMonitorDirZims(monitorDir, newDir.values());
     }
 }
 
-void Library::asyncLoadMonitorDir(QString dir)
+void Library::asyncUpdateFromDir(QString dir)
 {
     QtConcurrent::run( [=]() {
-        loadMonitorDir(dir);
+        updateFromDir(dir);
     });
 }
 
diff --git a/src/library.h b/src/library.h
index 45d113a..b741c67 100644
--- a/src/library.h
+++ b/src/library.h
@@ -11,6 +11,7 @@
 #include <QObject>
 #include <QSharedPointer>
 #include <QMap>
+#include <QMutex>
 
 #define TQS(v) (QString::fromStdString(v))
 #define FORWARD_GETTER(METH) QString METH() const { return TQS(mp_book->METH()); }
@@ -34,14 +35,14 @@ public:
     QStringList listBookIds(const kiwix::Filter& filter, kiwix::supportedListSortBy sortBy, bool ascending) const;
     const std::vector<kiwix::Bookmark> getBookmarks(bool onlyValidBookmarks = false) const { return m_library.getBookmarks(onlyValidBookmarks); }
     QStringList getLibraryZimsFromDir(QString dir) const;
-    void setMonitorDirZims(QStringList zimList);
+    void setMonitorDirZims(QString monitorDir, QStringList zimList);
     void addBookToLibrary(kiwix::Book& book);
     void removeBookFromLibraryById(const QString& id);
     void addBookmark(kiwix::Bookmark& bookmark);
     void removeBookmark(const QString& zimId, const QString& url);
     void save();
-    void loadMonitorDir(QString dir);
-    void asyncLoadMonitorDir(QString dir);
+    void updateFromDir(QString dir);
+    void asyncUpdateFromDir(QString dir);
     kiwix::Library& getKiwixLibrary() { return m_library; }
 public slots:
     const kiwix::Book& getBookById(QString id) const;
@@ -51,9 +52,10 @@ signals:
     void bookmarksChanged();
 
 private:
+    QMutex m_updateFromDirMutex;
     kiwix::Library m_library;
     QString m_libraryDirectory;
-    QStringList m_monitorDirZims;
+    QMap<QString, QStringList> m_knownZimsInDir;
 friend class LibraryManipulator;
 };