diff --git a/libraries/DNSServer/src/DNSServer.h b/libraries/DNSServer/src/DNSServer.h
index a10ef9eaaf1..a8de0eff73b 100644
--- a/libraries/DNSServer/src/DNSServer.h
+++ b/libraries/DNSServer/src/DNSServer.h
@@ -66,8 +66,8 @@ struct DNSHeader
 
 struct DNSQuestion
 {
-  uint8_t   QName[255] ;
-  int8_t    QNameLength ; 
+  uint8_t   QName[256] ; //need 1 Byte for zero termination!
+  uint8_t   QNameLength ; 
   uint16_t  QType ; 
   uint16_t  QClass ; 
 } ; 
@@ -106,4 +106,4 @@ class DNSServer
     void replyWithIP();
     void replyWithCustomCode();
 };
-#endif
\ No newline at end of file
+#endif