Support intro
Sorry to hear you’re facing problems. 
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Getting help
In order to help you as efficiently (and quickly!) as possible, please fill in as much of the below requested information as you can.
Before clicking submit: Please check if your query is already addressed via the following resources:
- Official documentation (searchable and regularly updated)
- How to topics and FAQs
- Forum search
(Utilizing these existing resources is typically faster. It also helps reduce the load on our generous volunteers while elevating the signal to noise ratio of the forums otherwise arising from the same queries being posted repeatedly).
Some or all of the below information will be requested if it isn’t supplied; for fastest response please provide as much as you can. 
The Basics
- Nextcloud Server version (e.g., 29.x.x):
31.0.2.1
- Operating system and version (e.g., Ubuntu 24.04):
Debian 12
- Web server and version (e.g, Apache 2.4.25):
replace me
- Reverse proxy and version _(e.g. nginx 1.27.2)
replace me
- PHP version (e.g, 8.3):
8.3
- Is this the first time you’ve seen this error? (Yes / No):
Yes
- When did this problem seem to first start?
Once I put NCP behind the firewall. When it was not firewalled I had no problem.
- Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.)
Proxmox NCP lxc installation script
- Are you using CloudfIare, mod_security, or similar? (Yes / No)
No
Summary of the issue you are facing:
Well, the subject line is pretty self-explanatory. I did a new install of NCP and have not used it for anything thus far - i.e. the system is as it was installed. I did run through the NextCloudPi Wizard on the NCP Panel and said that I did want to access Nextcloud from outside my house (i.e. behind a firewall) and that I would config the firewall manually. I configured three forwarding rules on the OpenWrt firewall for NCP’s ports 80 (8080 → 80), 443 (8443 → 443) and 4443 (4443 → 4443). These are essentially the same as the port forwards I have for a bunch of other services running on my Proxmox host, all of which work perfectly.
If I try to get to NCP’s port 80, Firefox’s “Unable to connect” page comes up. However, when I try to connect to 443 NCP kics out the “Access through untrusted domain” page - i.e. the firewall forwarding rule does actually work. Interestingly, when I try connecting to the NPC Panel via port 4443 the connection works fine and I can login.
Steps to replicate it (hint: details matter!):
I read the documentation about trusted domains in config.php and then edited the file to add the ip address of my laptop - 192.168.1.123.
The trusted domains section of the config.php file is now as follows:
array (
0 => ‘localhost’,
1 => ‘10.50.50.229’,
2 => ‘192.168.1.123’,
3 => ‘nextcloudpi’,
5 => ‘nextcloudpi.local’,
5 => ‘nextcloudpi.local’,
7 => ‘nextcloudpi’,
8 => ‘nextcloudpi.lan’,
11 => ‘89.92.2.142’,
14 => ‘nextcloud.ororke.net’,
),
You’d have thought that’s work but it didn’t. I still get nothing when trying to access port 80 and the “Access through untrusted domain” page when connecting via port 443.
Log entries
Nextcloud
Please provide the log entries from your Nextcloud log that are generated during the time of problem (via the Copy raw option from Administration settings->Logging screen or from your nextcloud.log located in your data directory). Feel free to use a pastebin/gist service if necessary.
PASTE HERE
Web Browser
If the problem is related to the Web interface, open your browser inspector Console and Network tabs while refreshing (reloading) and reproducing the problem. Provide any relevant output/errors here that appear.
PASTE
Web server / Reverse Proxy
The output of your Apache/nginx/system log in /var/log/____:
PASTE HERE
Configuration
Nextcloud
The output of occ config:list system or similar is best, but, if not possible, the contents of your config.php file from /path/to/nextcloud is fine (make sure to remove any identifiable information!):
PASTE HERE
Apps
The output of occ app:list (if possible).
Tips for increasing the likelihood of a response
- Use the
preformatted textformatting option in the editor for all log entries and configuration output. - If screenshots are useful, feel free to include them.
- If possible, also include key error output in text form so it can be searched for.
- Try to edit log output only minimally (if at all) so that it can be ran through analyzers / formatters by those trying to help you.