I had the same problem, for me the issue was that the client address was not whitelisted under ‘trusted_domains’ in the config/config.php file.
Might not be advisable security wise, but for my situation setting a wildcard is the solution
Yesterday I loaded a backup from a previous state where it still worked. However, there is now the problem that I was logged out as an admin and also have no way of logging in again.
So I reinstalled NC. It works fine without installing any apps. But as soon as I install an app, there are problems again.
At the moment I only installed the antivirus and the GeoBlocker. You can still log in, but as soon as you switch from login to the dashboard, the loading process takes about 3 minutes.
As soon as I install more apps, the problem reappears that the login is canceled.
@wwe I only noticed because I created a new user and he described the problem to me.
Then I created an account for testing.
@bigheadlarry thanks for the hint. However, I have the problem that I am not familiar with programming. I use a ready-made server from Syncloud.
do you experience high usage of system resources? especially antivirus could cause system slow-down… does the problem go away if you disable both this apps?