diff --git a/cgi-bin/core/doctype/search_criteria/search_criteria.py b/cgi-bin/core/doctype/search_criteria/search_criteria.py
index 00e5eb4330..15cfa703c7 100644
--- a/cgi-bin/core/doctype/search_criteria/search_criteria.py
+++ b/cgi-bin/core/doctype/search_criteria/search_criteria.py
@@ -28,7 +28,7 @@ class DocType:
 
 	def validate(self):
 		if sql("select name from `tabSearch Criteria` where criteria_name=%s and name!=%s", (self.doc.criteria_name, self.doc.name)):
-			webnots.msgprint("Criteria Name '%s' already used, please use another name" % self.doc.criteria_name, raise_exception = 1)
+			webnotes.msgprint("Criteria Name '%s' already used, please use another name" % self.doc.criteria_name, raise_exception = 1)
 
 	def on_update(self):
 		self.set_module()
@@ -72,4 +72,4 @@ class DocType:
 		if os.path.exists(os.path.join(path, old_name + extn)):
 			os.system('cp %s %s' % (os.path.join(path, old_name + extn), \
 			os.path.join(get_module_path(self.doc.module), 'search_criteria', scrub(self.doc.name), scrub(self.doc.name) + extn)))
-	
\ No newline at end of file
+	
diff --git a/cgi-bin/webnotes/utils/nestedset.py b/cgi-bin/webnotes/utils/nestedset.py
index 13af8ec4de..97cf156074 100644
--- a/cgi-bin/webnotes/utils/nestedset.py
+++ b/cgi-bin/webnotes/utils/nestedset.py
@@ -65,7 +65,11 @@ def update_add_node(doctype, name, parent, parent_field):
 	webnotes.conn.sql("update `tab%s` set rgt = rgt+2 where rgt >= %s" %(doctype,right))
 	webnotes.conn.sql("update `tab%s` set lft = lft+2 where lft >= %s" %(doctype,right))
 	
-	#$ update index of new node
+	# update index of new node
+	if webnotes.conn.sql("select * from `tab%s` where lft=%s or rgt=%s"% (doctype, right, right+1)):
+		webnotes.msgprint("Nested set error. Please send mail to support")
+		raise Exception
+
 	webnotes.conn.sql("update `tab%s` set lft=%s, rgt=%s where name='%s'" % (doctype,right,right+1,name))
 	return right