Update nextcloud 15.0.2 to 16.0.1 check for expected files

Im trying update nextcloud from 15.0.2 to 16.0.1 and update stop in “check for expected files” when fount this file -> .htty6vdhemift.data

Any idea?

It looks like a temporary directory to me, which has been created during the update. Check which data it contains and move it away from the Nextcloud web-root to get the error fixed. I would expect that your Nextcloud instance still works as expected as long as a separate datadirectory still exists.