What the padlock protects, the visual ways to get a real certificate on hosting and appliances, and how to treat certificate warnings.
Your cloud login page asks for the password that guards every file you own. Whether that password travels readable or encrypted is decided by one thing: HTTPS, the padlock. This page explains what it protects in plain words, the no-command ways to get a real certificate on both install routes, and the warning page you should never train yourself to ignore.
Without HTTPS, your ownCloud password and your files travel between your browser and the server in a form that other devices on the path can read. On your own home network the audience is small - your family and your router. The moment the cloud is reachable from the internet, the audience becomes every network between your visitor and your server. That is the honest line: a home-only cloud on plain HTTP is a small risk; an internet-facing cloud on plain HTTP is not a risk, it is a leak waiting for a date.
What matters is not which button - it is that the certificate is real and automatic-renewing, because an expired certificate trains everyone to click through warnings, which is worse than no warning at all.
Fresh visual installs often start with a self-signed certificate - encryption with no proof of identity - and the browser shows a full-page warning. That warning is the system working as designed. For a first evening of testing on your own network it is understandable to proceed and look around; as a permanent habit it is teaching yourself and your family to ignore the one alarm that also fires during a real attack. Replace it with a real certificate before the cloud becomes part of daily life, and never enter the admin password on a warning page from outside your home.
Once HTTPS works, use the https:// address everywhere: bookmarks, the desktop client and the phone apps. If a client still points at the old http:// address, it is still sending your password the readable way even though the padlock exists. One address, with the padlock, used by everything - that is the whole discipline.
The video installs the cloud - this page makes its front door safe to type a password into.
Watch Full VideoThe risk is smaller at home, because the path between your devices and the server stays inside your own network. But browsers, clients and family habits all carry over to outside use, and a self-signed warning clicked through at home becomes a warning clicked through anywhere. HTTPS at home is cheap insurance and good training.
Usually because the certificate is self-signed, expired, or made out for a different address than the one you typed. The browser is not saying encryption failed - it is saying identity is unproven. The fix is a real certificate for your exact address, not a louder click on the warning.
Yes. It is a real, browser-trusted certificate - the same trust level as the padlock on major websites. Its short lifetime is handled by automatic renewal, which your hosting panel or appliance sets up when you enable it.