I have a Synology DS410j with DSM 5.2-5967 Update 2 (Latest for this unit).
I do not have any website on it, it is mostly used with PhotoStation to show images public.
It has worked for years until now with https and 5001, but now It seems that I have to renew/install a new certificate.
(Message: Your connection is not private) With Android app DS photo it still works fine, but not on Windows PCs with several browsers.
I have exported server.csr and server.key, but I can’t figure out how to send the file to Let’s Encrypt, which I have been recommended.
In newer DSMs the option for Let’s Encrypt is implemented, but it seems that i can’t upgrade to DSM 6 on my 6-7 years old Synology.
So what can I do to get my Synology back in business?