diff --git a/src/contentmanager.cpp b/src/contentmanager.cpp
index da1c5db..31bd3d0 100644
--- a/src/contentmanager.cpp
+++ b/src/contentmanager.cpp
@@ -864,6 +864,21 @@ void ContentManager::asyncUpdateLibraryFromDir(QString dir)
     });
 }
 
+void ContentManager::handleDisappearedZimFiles(const QStringSet& zimPaths)
+{
+    const auto kiwixLib = mp_library->getKiwixLibrary();
+    for (auto bookPath : zimPaths) {
+        try {
+            DBGOUT("directory monitoring: file disappeared: " << bookPath);
+            const auto book = kiwixLib->getBookByPath(bookPath.toStdString());
+            handleDisappearedZimFile(QString::fromStdString(book.getId()));
+        } catch (const std::exception& err) {
+            DBGOUT("directory monitoring: "
+                   "error while dropping the disappeared book: " << err.what());
+        }
+    }
+}
+
 void ContentManager::updateLibraryFromDir(QString monitorDir)
 {
     typedef Library::QStringSet QStringSet;
@@ -880,25 +895,17 @@ void ContentManager::updateLibraryFromDir(QString monitorDir)
     const auto kiwixLib = mp_library->getKiwixLibrary();
     kiwix::Manager manager(kiwixLib);
     bool needsRefresh = !removedZims.empty();
-    for (auto bookPath : removedZims) {
-        try {
-            DBGOUT("ContentManager::updateLibraryFromDir(): "
-                    << "file disappeared: " << bookPath);
-            const auto book = kiwixLib->getBookByPath(bookPath.toStdString());
-            handleDisappearedZimFile(QString::fromStdString(book.getId()));
-        } catch (...) {}
-    }
+    handleDisappearedZimFiles(removedZims);
     for (auto bookPath : addedZims) {
         if ( mp_library->isBeingDownloadedByUs(bookPath) ) {
-            DBGOUT("ContentManager::updateLibraryFromDir(): " << bookPath
+            DBGOUT("directory monitoring: " << bookPath
                     << " ignored since it is being downloaded by us.");
         } else {
-            DBGOUT("ContentManager::updateLibraryFromDir(): "
-                   << "file appeared: " << bookPath);
+            DBGOUT("directory monitoring: file appeared: " << bookPath);
             const bool added = manager.addBookFromPath(bookPath.toStdString());
-            DBGOUT("                                        "
+            DBGOUT("                     "
                    << (added ? "and was added" : "but could not be added")
-                   << " to the library");
+                   << "to the library");
             needsRefresh |= added;
         }
     }
diff --git a/src/contentmanager.h b/src/contentmanager.h
index e92a158..b25a266 100644
--- a/src/contentmanager.h
+++ b/src/contentmanager.h
@@ -19,6 +19,7 @@ public: // types
     typedef QList<QPair<QString, QString>> FilterList;
     typedef ContentManagerModel::BookInfo     BookInfo;
     typedef ContentManagerModel::BookInfoList BookInfoList;
+    typedef Library::QStringSet QStringSet;
 
     enum class BookState
     {
@@ -69,7 +70,7 @@ public: // functions
     QStringList getCategories() const { return m_categories; }
     LanguageList getLanguages() const { return m_languages; }
 
-    void setMonitorDirZims(QString monitorDir, Library::QStringSet zimList);
+    void setMonitorDirZims(QString monitorDir, QStringSet zimList);
     void asyncUpdateLibraryFromDir(QString dir);
 
 signals:
@@ -117,6 +118,7 @@ private: // functions
     void setCategories();
     void setLanguages();
     void updateLibraryFromDir(QString dir);
+    void handleDisappearedZimFiles(const QStringSet& zimPaths);
     void handleDisappearedZimFile(QString bookId);
 
     // Get the book with the specified id from
@@ -148,7 +150,7 @@ private: // data
     QMutex remoteLibraryLocker;
 
     QMutex m_updateFromDirMutex;
-    QMap<QString, Library::QStringSet> m_knownZimsInDir;
+    QMap<QString, QStringSet> m_knownZimsInDir;
 };
 
 #endif // CONTENTMANAGER_H