Login canceled by app / Login durch App abgebrochen

Good afternoon dear community,
For a few days now, I have had the problem that I and other users can no longer log in via the Internet browser.

As soon as you enter your username and password when logging in, it takes a few seconds and then the error message appears: “Login aborted by app”.

I’m still logged in via another browser and everything works fine there. Merely a new registration is obviously not possible.

Does anyone happen to know how to fix the error or what could be the reason?

any error in logs?
did you have enabled any additional security methods like two-factor?
did you try creating a new user - can this new user login?

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?