I searching for an alternative way of certificates for this SSLClient, instead of the loading it with PROGMEM. I´ve seen some functions like loadCA() etc. which is expecting a stream as parameter. I´ve tried it with several AWS IoT certificate files from SPIFFS folder but it won’t work. The error contains this:

X509 - The CRT/CRL/CSR format is invalid

First, I thought the problem is the format of the certificates. But in contrast the version with the PROGMEM from a header file is working.

Maybe someone has an alternative way of loading the certificates from the flash.