diff --git a/nwfilters/templates/nwfilter.html b/nwfilters/templates/nwfilter.html
index 1f7c7b0..0d2e2f1 100644
--- a/nwfilters/templates/nwfilter.html
+++ b/nwfilters/templates/nwfilter.html
@@ -65,7 +65,7 @@
              <div class="form-group">
                 <label>{% trans "Filter:" %}</label>
                  <select id="nwfilter_select" name="nwfilters_select" class="form-control">
-                    <option value="None" selected>None</option>
+                    <option value="" selected>None</option>
                     {% for nwf in nwfilters_all %}
                         <option value="{{ nwf.name }}">{{ nwf.name }}</option>
                     {% endfor %}
diff --git a/nwfilters/views.py b/nwfilters/views.py
index 5fa39f5..99686ed 100644
--- a/nwfilters/views.py
+++ b/nwfilters/views.py
@@ -10,7 +10,9 @@ from django.contrib.auth.decorators import login_required
 from computes.models import Compute
 from vrtManager import util
 from vrtManager.nwfilters import wvmNWFilters, wvmNWFilter
+from vrtManager.instance import wvmInstances, wvmInstance
 from libvirt import libvirtError
+from logs.views import addlogmsg
 
 
 @login_required
@@ -33,9 +35,6 @@ def nwfilters(request, compute_id):
                            compute.password,
                            compute.type)
 
-        for nwf in conn.get_nwfilters():
-            nwfilters_all.append(conn.get_nwfilter_info(nwf.name()))
-
         if request.method == 'POST':
             if 'create_nwfilter' in request.POST:
                 xml = request.POST.get('nwfilter_xml', '')
@@ -56,29 +55,58 @@ def nwfilters(request, compute_id):
                             raise Exception(error_msg)
                     else:
                         try:
+                            msg = _("Creating NWFilter: %s" % name)
                             conn.create_nwfilter(xml)
-                            return HttpResponseRedirect(request.get_full_path())
+                            addlogmsg(request.user.username, compute.hostname, msg)
                         except libvirtError as lib_err:
                             error_messages.append(lib_err.message)
+                            addlogmsg(request.user.username, compute.hostname, lib_err.message)
+
             if 'del_nwfilter' in request.POST:
                 name = request.POST.get('nwfiltername','')
+                msg = _("Deleting NWFilter: %s" % name)
+                in_use = False
                 nwfilter = conn.get_nwfilter(name)
-                if nwfilter:
+
+                is_conn = wvmInstances(compute.hostname, compute.login, compute.password, compute.type)
+                instances = is_conn.get_instances()
+                for inst in instances:
+                #    if in_use: break
+                    i_conn = wvmInstance(compute.hostname, compute.login, compute.password, compute.type, inst)
+                    dom_filterrefs = i_conn.get_filterrefs()
+
+                    if name in dom_filterrefs:
+                        in_use = True
+                        msg = _("NWFilter is in use by %s. Cannot be deleted." % inst)
+                        error_messages.append(msg)
+                        addlogmsg(request.user.username, compute.hostname, msg)
+                        i_conn.close()
+                        break
+
+                is_conn.close()
+                if nwfilter and not in_use:
                     nwfilter.undefine()
-                return HttpResponseRedirect(request.get_full_path())
+                    addlogmsg(request.user.username, compute.hostname, msg)
 
             if 'cln_nwfilter' in request.POST:
+
                 name = request.POST.get('nwfiltername','')
                 cln_name = request.POST.get('cln_name', name + '-clone')
 
                 conn.clone_nwfilter(name,cln_name)
-                return HttpResponseRedirect(request.get_full_path())
+                msg = _("Cloning NWFilter %s as %s" % (name, cln_name))
+                addlogmsg(request.user.username, compute.hostname, msg)
+
+        for nwf in conn.get_nwfilters():
+            nwfilters_all.append(conn.get_nwfilter_info(nwf.name()))
 
         conn.close()
     except libvirtError as lib_err:
         error_messages.append(lib_err)
+        addlogmsg(request.user.username, compute.hostname, lib_err)
     except Exception as err:
         error_messages.append(err)
+        addlogmsg(request.user.username, compute.hostname, err)
 
     return render(request, 'nwfilters.html', {'error_messages': error_messages,
                                               'nwfilters': nwfilters_all,
diff --git a/vrtManager/instance.py b/vrtManager/instance.py
index d63d36c..ca5568f 100644
--- a/vrtManager/instance.py
+++ b/vrtManager/instance.py
@@ -187,6 +187,19 @@ class wvmInstance(wvmConnect):
         title = util.get_xml_path(self._XMLDesc(0), "/domain/title")
         return title if title else ''
 
+    def get_filterrefs(self):
+
+        def filterrefs(ctx):
+            result = []
+            for net in ctx.xpath('/domain/devices/interface'):
+                filterref = net.xpath('filterref/@filter')
+                if filterref:
+                    result.append(filterref[0])
+            return result
+
+        return util.get_xml_path(self._XMLDesc(0), func=filterrefs)
+
+
     def get_description(self):
         description = util.get_xml_path(self._XMLDesc(0), "/domain/description")
         return description if description else ''