diff --git a/lib/Slic3r/GUI.pm b/lib/Slic3r/GUI.pm
index e4cb2760..b590a5de 100644
--- a/lib/Slic3r/GUI.pm
+++ b/lib/Slic3r/GUI.pm
@@ -170,7 +170,7 @@ sub OnInit {
         EVT_MENU($frame, MI_CONF_WIZARD, sub { $self->{skeinpanel}->config_wizard });
         EVT_MENU($frame, MI_WEBSITE, sub { Wx::LaunchDefaultBrowser('http://slic3r.org/') });
         EVT_MENU($frame, MI_VERSIONCHECK, sub { Slic3r::GUI->check_version(manual => 1) });
-        EVT_MENU($frame, MI_DOCUMENTATION, sub { Wx::LaunchDefaultBrowser('https://manual.slic3r.org/') });
+        EVT_MENU($frame, MI_DOCUMENTATION, sub { Wx::LaunchDefaultBrowser('http://manual.slic3r.org/') });
         EVT_MENU($frame, wxID_ABOUT, \&about);
     }