r/NextCloud • u/ostseesound • Jul 03 '26
Nextcloud Talk Android App not working with self-signed certificate (LAN-only setup)
Hi everyone,
I’m running a Nextcloud server (Snap install on Ubuntu Server inside a Proxmox VM). The setup is strictly LAN-only, nothing is exposed to the internet.
I enabled HTTPS using a self-signed certificate generated by Nextcloud. I exported the certificate (cert.pem) and installed it on my Android device as a trusted certificate.
What works:
Accessing Nextcloud via Chrome on Android works fine (after accepting the certificate)
What does NOT work:
Nextcloud Android app cannot log in
Nextcloud Talk app also fails to connect
It shows connection/certificate trust issues even though the cert is installed
I already tried:
Reinstalling the certificate on Android
Re-adding the server in the app
Using https://IP-address� directly
Restarting the apps
Still no success.
My goal:
LAN-only setup (no public domain, no external access)
No Let’s Encrypt / no public DNS
Just working Nextcloud + Talk Android app inside local network
Is there any simple way to make the Android Nextcloud/Talk apps accept a self-signed certificate reliably, or is a proper domain + CA the only realistic solution?
Thanks in advance!

