diff --git a/src/diffpy/pdfgui/gui/mainframe.py b/src/diffpy/pdfgui/gui/mainframe.py
index bbe63bca..b8b7f7f1 100644
--- a/src/diffpy/pdfgui/gui/mainframe.py
+++ b/src/diffpy/pdfgui/gui/mainframe.py
@@ -2523,10 +2523,7 @@ def onDocumentation(self, event):
         """Show information about the documentation."""
         import webbrowser
 
-        from six.moves.urllib.request import pathname2url
-
-        url = "file://" + pathname2url(docMainFile)
-        webbrowser.open(url)
+        webbrowser.open(docMainFile)
         return
 
     # MISC INTERACTION ITEMS
diff --git a/src/diffpy/pdfgui/gui/pdfguiglobals.py b/src/diffpy/pdfgui/gui/pdfguiglobals.py
index cbfdc911..94811ce0 100644
--- a/src/diffpy/pdfgui/gui/pdfguiglobals.py
+++ b/src/diffpy/pdfgui/gui/pdfguiglobals.py
@@ -55,7 +55,7 @@
 APPDATADIR = os.path.abspath(APPDATADIR)
 
 # Location of the HTML manual
-docMainFile = os.path.join(APPDATADIR, "doc/manual/pdfgui.html")
+docMainFile = "https://www.diffpy.org/diffpy.pdfgui/manual.html"
 
 del _upbasedir
 del _development_mode