diff --git a/confluent_server/confluent/plugins/hardwaremanagement/affluent.py b/confluent_server/confluent/plugins/hardwaremanagement/affluent.py
index 71cecea9..ea169b3b 100644
--- a/confluent_server/confluent/plugins/hardwaremanagement/affluent.py
+++ b/confluent_server/confluent/plugins/hardwaremanagement/affluent.py
@@ -49,7 +49,8 @@ class WebClient(object):
             results.put(msg.ConfluentTargetInvalidCredentials(self.node, 'Unable to authenticate'))
             return {}
         elif status != 200:
-            results.put(msg.ConfluentNodeError(self.node, 'Unknown error: ' + rsp + ' while retrieving ' + url))
+            #must be str not bytes
+            results.put(msg.ConfluentNodeError(self.node, 'Unknown error: {} while retrieving {}'.format(rsp, url)))
             return {}
         return rsp
     
@@ -192,4 +193,4 @@ def retrieve_health(configmanager, creds, node, results, element):
     hinfo = wc.fetch('/affluent/health', results) 
     if hinfo:
         results.put(msg.HealthSummary(hinfo.get('health', 'unknown'), name=node))
-        results.put(msg.SensorReadings(hinfo.get('sensors', []), name=node))
\ No newline at end of file
+        results.put(msg.SensorReadings(hinfo.get('sensors', []), name=node))