diff --git a/pyghmi/ipmi/oem/lenovo/config.py b/pyghmi/ipmi/oem/lenovo/config.py
index 2a9844a1..a7b20dbb 100644
--- a/pyghmi/ipmi/oem/lenovo/config.py
+++ b/pyghmi/ipmi/oem/lenovo/config.py
@@ -45,7 +45,7 @@ SIZE_COMMAND = [0x06]
 
 
 def fromstring(inputdata):
-    if '!entity' in inputdata:
+    if b'!entity' in inputdata.lower():
         raise Exception('Unsupported XML')
     return etree.fromstring(inputdata)
 
diff --git a/pyghmi/ipmi/oem/lenovo/nextscale.py b/pyghmi/ipmi/oem/lenovo/nextscale.py
index 9b4e47e4..020e24ec 100644
--- a/pyghmi/ipmi/oem/lenovo/nextscale.py
+++ b/pyghmi/ipmi/oem/lenovo/nextscale.py
@@ -38,7 +38,7 @@ except NameError:
 
 
 def fromstring(inputdata):
-    if '!entity' in inputdata.lower():
+    if b'!entity' in inputdata.lower():
         raise Exception('!ENTITY not supported in this interface')
     return rfromstring(inputdata)