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Sorry to hear you’re facing problems 
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example
Or for longer, use three backticks above and below the code snippet:
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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 
Nextcloud version (eg, 20.0.5): 21.0.2.1
Operating system and version (eg, Ubuntu 20.04): Debian 10
Apache or nginx version (eg, Apache 2.4.25): apache 2.4.38 (Debian)PHP version _(eg, 7.4)_:7.3 FPM/Fast CGI`
The issue you are facing:
Using CloudNotes 3.3.0 (2857) on iOS 14.6 for writing notes and hosting them (approx 500 pcs) on my rootserver (hetzner core i7 2.7 ghz, 16gb ram and 4 x 4 tb in raid 5). Server runs Debian 10 with ispconfig and Apache/maria dB (Version 15.1 Distrib 10.3.27-Mariann ). Servus several domains for me and some friends. Nextcloud 21 runs in own domain / virtual server made by ispconfig with let’s encrypt cert.
app “Brute-force settings” is disabled.
app “Default encryption module” is disabled.
pretty urls are added.
/index.php is added to servername in cloudnotes.
username and password is right one — when I hit „connect“ in cloudnotes it logs in, the green window appear, I press „sync“, it starts doing something.
Until last Friday it successfully synced, notes were editable and changes appeared instantaneously in Webbrowser I am logged into nc too.
Suddenly out of nothing during Friday syncing stopped and it showed error 401 again and again. same when I try to reconnect.
same with 3 other Nextcloud I am running on other machines. Same on iPad.
same with fresh User with no notes in same Nextcloud.
same after erasing local cloudnotes database on iPad and iPhone.
No entry’s in Apache logs.
In Nextcloud log only this:
„ warning core login failed ‚username (ipv4)“
When I try to reconnect cloudnotes to nc server log is flooded with many of these within a second.
Problem occurs both in home network and thru LTE ( deutsche Telekom p v6 only)
login into Nextcloud in Webbrowser chrome, Safari on iOS and on mac with username and password tried in cloudnotes runs without any problems.
since same with 4 different Nextcloud and same on iPad and iPhone and no Problem in Webbrowsers there must be a mistake in cloudnotes iOS app.
Is this the first time you’ve seen this error? (Y/N): y
Steps to replicate it:
- login into Nextcloud with cloudnotes
- hit sync
- app says error 401
The output of your Nextcloud log in Admin > Logging:
„ warning core login failed ‚username (ipv4)“
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
'instanceid' => 'xxx',
'passwordsalt' => 'xxx',
'secret' => 'xxx',
'trusted_domains' =>
array (
0 => 'xxx',
),
'datadirectory' => '/var/www/clients/xxx /data',
'dbtype' => 'mysql',
'version' => '21.0.2.1',
'overwrite.cli.url' => 'https://xxx',
'dbname' => 'xxx',
'dbhost' => 'localhost',
'dbport' => '',
'dbtableprefix' => 'oc_',
'mysql.utf8mb4' => true,
'dbuser' => 'xxx',
'dbpassword' => 'xxx',
'installed' => true,
'memcache.local' => '\\OC\\Memcache\\APCu',
'default_phone_region' => 'DE',
'filelocking.enabled' => false,
'auth.bruteforce.protection.enabled' => false,
'maintenance' => false,
The output of your Apache/nginx/system log in /var/log/____:
No output