diff --git a/src/HomeSpan.cpp b/src/HomeSpan.cpp
index 2de8c34..78929dd 100644
--- a/src/HomeSpan.cpp
+++ b/src/HomeSpan.cpp
@@ -865,7 +865,7 @@ void Span::processSerialCommand(const char *c){
       int nErrors=0;
       int nWarnings=0;
       
-      unordered_set<uint32_t> aidValues;
+      vector<uint32_t> aidValues;
       char pNames[][7]={"PR","PW","EV","AA","TW","HD","WR"};
 
       for(auto acc=Accessories.begin(); acc!=Accessories.end(); acc++){
@@ -875,10 +875,10 @@ void Span::processSerialCommand(const char *c){
         if(acc==Accessories.begin() && (*acc)->aid!=1)
           LOG0("   *** ERROR #%d!  AID of first Accessory must always be 1 ***\n",++nErrors);
 
-        if(aidValues.find((*acc)->aid)!=aidValues.end())
+        if(std::find(aidValues.begin(),aidValues.end(),(*acc)->aid)!=aidValues.end())
           LOG0("   *** ERROR #%d!  AID already in use for another Accessory ***\n",++nErrors);
         
-        aidValues.insert((*acc)->aid);
+        aidValues.push_back((*acc)->aid);
 
         for(auto svc=(*acc)->Services.begin(); svc!=(*acc)->Services.end(); svc++){
           LOG0("   \u279f Service %s:  IID=%d, %sUUID=\"%s\"\n",(*svc)->hapName,(*svc)->iid,(*svc)->isCustom?"Custom-":"",(*svc)->type);
diff --git a/src/HomeSpan.h b/src/HomeSpan.h
index a61b5ca..00636d0 100644
--- a/src/HomeSpan.h
+++ b/src/HomeSpan.h
@@ -37,7 +37,6 @@
 #include <Arduino.h>
 #include <unordered_map>
 #include <vector>
-#include <unordered_set>
 #include <list>
 #include <nvs.h>
 #include <ArduinoOTA.h>
@@ -55,7 +54,6 @@
 
 using std::vector;
 using std::unordered_map;
-using std::unordered_set;
 using std::list;
 
 enum {
diff --git a/src/Network.h b/src/Network.h
index 679ecfe..1cb17d4 100644
--- a/src/Network.h
+++ b/src/Network.h
@@ -28,11 +28,8 @@
 #pragma once
 
 #include <WiFi.h>
-#include <unordered_set>
 #include "Settings.h"
 
-using std::unordered_set;
-
 const int MAX_SSID=32;                              // max number of characters in WiFi SSID
 const int MAX_PWD=64;                               // max number of characters in WiFi Password