I've just acquired a Xerox 6505, and try since one week to add an email auth for scanning from the printer and deliver the scanned documents by email.
I tried my hotmail and gmail accounts, with our without SSL activated but didn't worked as expected.
Always I get the Error 016-503 ans when SSL is activated, I can't go on "CentreWare Internet Services" anymore as my Chrome / Firefox / Edge, see this new new "Secured" url as containing an invalid certificate.
Hopefully everything else work good (Print, copy, scan via ethernet as well).
Below is the setup I now use, in order to access "CentreWare Internet Services".
Thank you very much for your kind help!