PDFreactor can connect to servers using the HTTPS protocol. However, Java validates the server's certificate. This can cause issues e.g. during development where internal servers may use self-signed certificates, which are usually treated as insecure by Java. To avoid that you can use a more convenient approach by telling PDFreactor to automatically trust all SSL certificates:
PDFreactor Web Service
This is a server-side setting and applies to all conversions. It has to be configured using server parameters. More information can be found in the PDFreactor Web Service manual here: https://pdfreactor.com/product/doc/manual-ws.html#ssl-certificate-validation
PDFreactor Library
config.setSecuritySettings(new SecuritySettings() .setTrustAllConnectionCertificates(true));
More information can be found in the PDFreactor Library manual here: https://pdfreactor.com/product/doc/manual-lib.html#ssl-certificate-validation