ESP32 AP模式获取WiFi凭证时出现Association超时错误求助

我正在制作一个用于获取WiFi凭证的AP服务器，若等待约2分钟才连接AP或输入SSID与密码，会触发如下错误：

E (168130) wifi:Association refused temporarily, comeback time 268435 mSec
E (168130) wifi:Association comeback time (268435) mSec too long. max allowed 5000 mSec
E (168738) wifi:Association refused temporarily, comeback time 268435 mSec
E (168738) wifi:Association comeback time (268435) mSec too long. max allowed 5000 mSec

我输入的SSID与密码正确，但仍会出现该错误，再次输入相同信息却能成功连接。请问这是什么原因？

以下是我的完整代码（HTML部分过长已省略）：

#include <WiFi.h>
#include <WiFiClient.h>
#include <WebServer.h>

WebServer server(80);
const char PAGE_MAIN[] PROGMEM = R"=====(  html codes )=====";

String page = PAGE_MAIN; // Convert const char[] to String
boolean tryToConnect = true;

const char* accessPointName = "accespoint";      
const char* accessPointPassword = "accespointpassword"; 
char ssid[50];    
char password[50];  
String ssidlist = "";

void handleRoot() {
  server.send(200, "text/html", page); // Send the modified page
}

void handleSave() {
  String newSSID = server.arg("security");
  String newPassword = server.arg("password");
  tryToConnect = true;
  newSSID.toCharArray(ssid, sizeof(ssid));
  newPassword.toCharArray(password, sizeof(password));

  WiFi.disconnect(true); // Disconnect from the current network, forgetting it
  delay(100);
  
  Serial.println(ssid);
  Serial.println(password);
  WiFi.begin(ssid, password);

  Serial.print("Connecting...");
  unsigned long startTime = millis(); 
  while (WiFi.status() != WL_CONNECTED && tryToConnect) {
    delay(1000);
    Serial.print(".");
    if (millis() - startTime > 10000) {
      tryToConnect = false;
      Serial.println(""); 
      String response = "<html><head><meta http-equiv='Content-Type' content='text/html;charset=utf-8'></head>";
      response += "<body><h1>Wrong password, please try again</h1>";
      response += "<a href='/'>Go back</a></body></html>"; 
      server.send(200, "text/html", response);
      server.sendHeader("Location", "/", true);
      server.send(302, "text/plain", ""); 
    }
  }
if (WiFi.status() == WL_CONNECTED) {
    Serial.print("Connect, new IP address: ");
    Serial.println(WiFi.localIP());
    String response = "<html><head><meta http-equiv='Content-Type' content='text/html;charset=utf-8'></head>";
    response = "<body><h1>Password correct.</h1>";
    server.send(200, "text/html", response);
    delay(5000);
    server.stop();
    WiFi.softAPdisconnect(true);
  }
}

void wifiInit(){
  WiFi.softAP(accessPointName, accessPointPassword);
  Serial.println("Access point started.");

  // WiFi.scanNetworks will return the number of networks found
  int n = WiFi.scanNetworks();
  Serial.println("scan done");
  if (n == 0) {
      Serial.println("no networks found");
  } else {
    Serial.print(n);
    Serial.println(" networks found");
    for (int i = 0; i < n; ++i) {
      // Print SSID and RSSI for each network found
      //Serial.print(i + 1);
      //Serial.print(": ");
      //Serial.print(WiFi.SSID(i));   
      //Serial.println((WiFi.encryptionType(i) == WIFI_AUTH_OPEN)?" ":"*");
      delay(10);
      ssidlist += WiFi.SSID(i) + ",";
    }
  }
  page.replace("--ssidlist--", ssidlist); // Perform the replace operation
  Serial.println(ssidlist);
  Serial.println("");
  delay(2000);
  server.on("/", handleRoot);
  server.on("/save", handleSave);
  server.begin();
  Serial.print("Access point ip adress ");
  Serial.println(WiFi.softAPIP());
  
}

void setup() {
  Serial.begin(115200);

  while (!Serial) {
    ;
  }
  wifiInit();
}

void loop() {
  server.handleClient();
}

这个错误由ESP32 WiFi驱动的临时关联拒绝机制导致：

• 当设备长时间（如你这里的2分钟）处于AP模式未发起WiFi连接时，WiFi驱动内部会缓存无效的关联状态，或者目标AP可能因设备长时间无响应将其MAC地址临时加入黑名单。
• 首次尝试连接时，驱动读取到缓存的过长重试间隔（268435ms，远超允许的5000ms上限），直接拒绝连接请求。
• 再次输入信息时，WiFi.disconnect(true)强制清除了部分缓存状态，重置了重试计时器，因此能正常连接。

修改handleSave函数，在发起连接前彻底重置WiFi驱动状态，清除所有缓存的重试信息：

void handleSave() {
  String newSSID = server.arg("security");
  String newPassword = server.arg("password");
  tryToConnect = true;
  newSSID.toCharArray(ssid, sizeof(ssid));
  newPassword.toCharArray(password, sizeof(password));

  // 彻底重置WiFi状态：先关闭WiFi，再重新启用Station模式
  WiFi.mode(WIFI_OFF);
  delay(100);
  WiFi.mode(WIFI_STA);
  delay(100);
  
  Serial.println(ssid);
  Serial.println(password);
  WiFi.begin(ssid, password);

  // 后续连接逻辑保持不变...
}

另外，原代码中连续调用server.send(200)和server.send(302)会导致HTTP响应异常，建议保留302跳转即可：

if (millis() - startTime > 10000) {
  tryToConnect = false;
  Serial.println(""); 
  server.sendHeader("Location", "/", true);
  server.send(302, "text/plain", "连接超时，请重试"); 
}

内容的提问来源于stack exchange，提问作者Tryingtogetsome