WiFi Manager chapter in Build Web Servers book Q&A Forum › Category: ESP32 › WiFi Manager chapter in Build Web Servers book 0 Vote Up Vote Down Ron Kreymborg asked 2 years ago Compile fails with message: “undefined reference to mbedtls_md5_starts” 2 Answers 0 Vote Up Vote Down Sara Santos Staff answered 2 years ago Hi. Change on platformio.ini, the platform to espressif32@3.5.0 instead espressif32. Then, try to compile and upload again. Regards, Sara 0 Vote Up Vote Down Steen Spaten answered 9 months ago Thank you – it worked for me too