@Gabriel Michaud, you right, thank you. I messed up user scenarios here.

@Irina I think @marilizevanzyl71 is talking about the Encryption Certificates page where you can add your own certificates for PDF export signature, SFTP, etc --- is a self-signed certificate OK in such cases? For the Acumatica instance itself it would definitely create all sorts of problems as you point out, and there are services like Let’s Encrypt that provide trusted SSL certificates at no cost anyway.

Please note that self-signed certificates are not fully supported by Acumatica, thus you could have issues when using the mobile app, plug-ins, and integrations.

We recommend having certificates from trusted centers on Acumatica ERP sites.

@marilizevanzyl71 OpenSsl is the tool you want to use to generate your own self-signed certificates. The process is not trivial -- I searched online to find clean & simple instructions, I think this should help: https://www.claudiobernasconi.ch/2016/04/17/creating-a-self-signed-x509-certificate-using-openssl-on-windows/