Maybe it's a dumb question but I don't know how to solve this: we've got a web server with an SSL certificate for its domain. I can view this site, correctly from anywhere but when we are at the office, inside the intranet. When I connect a PC to their WiFi or wired network I get an invalid certificate error, but when I'm connected from outside world I see it perfectly. What do I need to configure/add to the network to make it use Internet and not the intranet to get to the domain? I would appreciate your suggestions. Thank you in advance.
Edit: I'm running an ownCloud instance on a webserver, and it has Let's Encrypt SSL certificate. When I point a browser from outside the intranet I see the https working perfecly. When I do it from a device inside the network, even though I use the domain name (just the same address I use from outside) I get a self-signed certificate notice. It doesn't matter what OS I'd use, but anyway I test it using my Linux laptop and another running Windows.