diff --git a/cps/templates/readpdf.html b/cps/templates/readpdf.html
index ac9eadd4..fd6c7570 100644
--- a/cps/templates/readpdf.html
+++ b/cps/templates/readpdf.html
@@ -43,7 +43,9 @@ See https://github.com/adobe-type-tools/cmap-resources
     <script type="text/javascript">
     window.addEventListener('webviewerloaded', function() {
         PDFViewerApplicationOptions.set('disableAutoFetch', true);
-        PDFViewerApplicationOptions.set('disableRange', true);
+        PDFViewerApplicationOptions.set('disableRange', false);
+        PDFViewerApplicationOptions.set('disableStream', true);
+        PDFViewerApplicationOptions.set('disablePreferences', true);
         PDFViewerApplicationOptions.set('cMapUrl', "{{ url_for('static', filename='cmaps/') }}");
         PDFViewerApplicationOptions.set('sidebarViewOnLoad', 0);
         PDFViewerApplicationOptions.set('imageResourcesPath', "{{ url_for('static', filename='css/images/') }}");
diff --git a/cps/web.py b/cps/web.py
index f02ac21e..0f925300 100644
--- a/cps/web.py
+++ b/cps/web.py
@@ -1161,7 +1161,14 @@ def serve_book(book_id, book_format, anyname):
     data = calibre_db.get_book_format(book_id, book_format.upper())
     if not data:
         return "File not in Database"
-    log.info('Serving book: %s', data.name)
+    
+    range_header = request.headers.get('Range', None)
+    if not range_header:
+        log.info('Serving book: %s', data.name)
+        response = make_response(send_from_directory(os.path.join(config.config_calibre_dir, book.path), data.name + "." + book_format))
+        response.headers['Accept-Ranges'] = 'bytes'
+        return response
+    
     if config.config_use_google_drive:
         try:
             headers = Headers()