Hi.
Can you double-check you’re using the recommended ESPAsyncWebServer and AsyncTCP libraries? We’re using the ones by ESP32Async. You can install them via Arduino IDE Boards Manager.
Also, make sure you dont’t have other versions of the library installed. You can go to the Arduino libraries folder and check if there are any other folders with other versions of the library.

Regards,
Sara

sketch_sep23a:112:18: error: no matching function for call to ‘AsyncWebServerRequest::send(int, const char [10], const char [671],

sketch_sep23a:112:18: error: no matching function for call to ‘AsyncWebServerRequest::send(int, const char [10], const char [671], String (&)(const String&))’
112 | request->send(200, “text/html”, index_html, processor);
| ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from C:\Users\capta\AppData\Local\Temp\arduino_modified_sketch_329666\sketch_sep23a.ino:10:
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:241:10: note: candidate: ‘void AsyncWebServerRequest::send(const String&, size_t, AwsResponseFiller, AwsTemplateProcessor)’
241 | void send(const String& contentType, size_t len, AwsResponseFiller callback, AwsTemplateProcessor templateCallback=nullptr);
| ^~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:241:72: note: no known conversion for argument 3 from ‘const char [671]’ to ‘AwsResponseFiller’ {aka ‘std::function’}
241 | void send(const String& contentType, size_t len, AwsResponseFiller callback, AwsTemplateProcessor templateCallback=nullptr);
| ~~~~~~~~~~~~~~~~~~^~~~~~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:236:10: note: candidate: ‘void AsyncWebServerRequest::send(AsyncWebServerResponse*)’
236 | void send(AsyncWebServerResponse *response);
| ^~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:236:10: note: candidate expects 1 argument, 4 provided
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:237:10: note: candidate: ‘void AsyncWebServerRequest::send(int, const String&, const String&)’
237 | void send(int code, const String& contentType=String(), const String& content=String());
| ^~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:237:10: note: candidate expects 3 arguments, 4 provided
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:238:10: note: candidate: ‘void AsyncWebServerRequest::send(FS&, const String&, const String&, bool, AwsTemplateProcessor)’
238 | void send(FS &fs, const String& path, const String& contentType=String(), bool download=false, AwsTemplateProcessor callback=nullptr);
| ^~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:238:19: note: no known conversion for argument 1 from ‘int’ to ‘AsyncWebServerRequest::FS&’ {aka ‘fs::FS&’}
238 | void send(FS &fs, const String& path, const String& contentType=String(), bool download=false, AwsTemplateProcessor callback=nullptr);
| ~~~~^~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:239:10: note: candidate: ‘void AsyncWebServerRequest::send(File, const String&, const String&, bool, AwsTemplateProcessor)’
239 | void send(File content, const String& path, const String& contentType=String(), bool download=false, AwsTemplateProcessor callback=nullptr);
| ^~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:239:20: note: no known conversion for argument 1 from ‘int’ to ‘AsyncWebServerRequest::File’ {aka ‘fs::File’}
239 | void send(File content, const String& path, const String& contentType=String(), bool download=false, AwsTemplateProcessor callback=nullptr);
| ~~~~~^~~~~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:240:10: note: candidate: ‘void AsyncWebServerRequest::send(Stream&, const String&, size_t, AwsTemplateProcessor)’
240 | void send(Stream &stream, const String& contentType, size_t len, AwsTemplateProcessor callback=nullptr);
| ^~~~
C:\Users\capta\Documents\Arduino\libraries\ESPAsyncWebServer-master\src/ESPAsyncWebServer.h:240:23: note: no known conversion for argument 1 from ‘int’ to ‘Stream&’
240 | void send(Stream &stream, const String& contentType, size_t len, AwsTemplateProcessor callback=nullptr);
| ~~~~~~~~^~~~~~

In another post of yours, I found your suggestion to downgrade the drivers of ESP32 to 3.0.7 and I did it without any improvement.
Please help me.
Thank you.

That’s great.

Thank you Sara

I have launched this application and it works fine. I will try to include it in my project.

Thanks and regards

I rolled back my ESP32 boards and it works now.

Thanks!

Hi.
Do you get more specific errors?
Regards,
Sara

Hi Sara!
Thank you for the response. I removed the ESP32 boards and redownloaded. Then I used the DOIT ESP32 DEVKIT V1 and everything compiled fine.

Unfortunately now, my Gmail email is failing to send when the threshold is breached.

The instructions mention both an SSL and TMS port but the code just has the SSL value of 465.

I’m digging into this now.

Hi.
Check the version of the ESP32 boards you have installed in Tools > Boards > Board Manager > ESP32.

Or are you using VS Code?

Regards
Sara

I am actually having issues with header files not being found. I’ve included the libraries as requested above but I am receiving this error:

ESP32_Mail_Client\src/ssl_client32.h:36:10: fatal error: mbedtls/net.h: No such file or directory

Hi.
check this tutorial: https://randomnerdtutorials.com/esp32-send-email-smtp-server-arduino-ide/
Regards
Sara