Explaining error

I am trying to understand why I see an error when starting Nextcloud (Internal server error).
The log file tells me a lot, but I am not able to understand:

{"reqId":"py7UWlaOsT8ferbqhqAM","level":3,"time":"2020-05-28T09:38:13+02:00","remoteAddr":"192.168.2.254","user":"guido","app":"index","method":"GET","url":"/apps/files/","message":{"Exception":"OCP\\Files\\NotFoundException","Message":"","Code":0,"Trace":[{"file":"/var/www/nextcloud/apps/files/lib/Controller/ViewController.php","line":139,"function":"getStorageInfo","class":"OC_Helper","type":"::"},{"file":"/var/www/nextcloud/apps/files/lib/Controller/ViewController.php","line":187,"function":"getStorageInfo","class":"OCA\\Files\\Controller\\ViewController","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":170,"function":"index","class":"OCA\\Files\\Controller\\ViewController","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":99,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/App.php","line":125,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Routing/RouteActionHandler.php","line":47,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"function":"__invoke","class":"OC\\AppFramework\\Routing\\RouteActionHandler","type":"->"},{"file":"/var/www/nextcloud/lib/private/Route/Router.php","line":299,"function":"call_user_func"},{"file":"/var/www/nextcloud/lib/base.php","line":1008,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"/var/www/nextcloud/index.php","line":38,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/nextcloud/lib/private/legacy/helper.php","Line":490,"CustomMessage":"--"},"userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.61 Safari/537.36","version":"18.0.4.2"}

Who can help me to understand and give me some hints what to do?

Best regards,
Guido

Here is the problem:

“app”: “index”,
“method”: “GET”,
“url”: “/apps/files/”,
“message”: {
“Exception”: “OCP\Files\NotFoundException”,
“Message”: “”,
“Code”: 0,
“Trace”: [
{

But I cannot see what you did and where you came to that point.

Thanks for your reply!
I created a ‘script’ (not an executable one, only a long list of commands) to build my Nextcloud.
I created the database, set up the admin user and add two other users using the occ command. The admin user was logged in, so that account is set properly. Then I log out the admin and log in as user #2 and get the error.

Now I try to figure out how to avoid these error.

Any help is appreciated.

Best regards,
Guido

Can you give (for testing) the user #2 admin rights - and then try to login?

User #2 is also an admin.
Using the regular browser mode I am able to login as admin user #1. user #2 reports the error when login.
Using the incognito browser mode I am not able to login as user #1 or user #2.

Is the datadirectory read- and writeable by the webserver user?