"Some files have not passed the integrity check"

[Kerasit]

Code integrity check - cannot be solved

The problem is solved. The two files seem to be exactly the same in two directories (admin and user). At some point the error display changed from “admin” to “user”. Since everything else was the same, I didn’t notice. Evil trap! Next, I moved the additional directory somewhere else, ran a new scan and moved the directory back. Now there is no more error message. Many thanks to everyone who helped me Should one generally copy the entire Nextcloud archive to the server …

You can try do a maintenance:repair with OCC.