diff --git a/octoprint/templates/settings.jinja2 b/octoprint/templates/settings.jinja2
index db03581..950689a 100644
--- a/octoprint/templates/settings.jinja2
+++ b/octoprint/templates/settings.jinja2
@@ -6,7 +6,7 @@
     <div class="modal-body">
         <div class="tabbable">
             <ul class="nav nav-list span4" id="settingsTabs">
-                <li class="active"><a href="#settings-serialConnection" data-toggle="tab">Serial Connection</a></li>
+                <li class="active"><a href="#settings_serialConnection" data-toggle="tab">Serial Connection</a></li>
                 <li><a href="#settings_printerParameters" data-toggle="tab">Printer Parameters</a></li>
                 <li><a href="#settings_webcam" data-toggle="tab">Webcam</a></li>
                 <li><a href="#settings_features" data-toggle="tab">Features</a></li>
diff --git a/octoprint/util/comm.py b/octoprint/util/comm.py
index 9e6a5c7..367bd4f 100644
--- a/octoprint/util/comm.py
+++ b/octoprint/util/comm.py
@@ -851,10 +851,13 @@ class MachineCom(object):
 
 	def _gcode_G0(self, cmd):
 		if 'Z' in cmd:
-			z = float(re.search('Z([0-9\.]*)', cmd).group(1))
-			if self._currentZ != z:
-				self._currentZ = z
-				self._callback.mcZChange(z)
+			try:
+				z = float(re.search('Z([0-9\.]*)', cmd).group(1))
+				if self._currentZ != z:
+					self._currentZ = z
+					self._callback.mcZChange(z)
+			except ValueError:
+				pass
 		return cmd
 	_gcode_G1 = _gcode_G0