While updating to owncloud 8.0.2-5 via
sudo apt-get update && sudo apt-get upgrade
and reloading the page within the webbrowser i got the message:
.htaccess file has the wrong version. Please upload the correct version. Maybe you forgot to replace it after updating?
I had to open the .htaccess file and changed the version number from 8.0.0 to 8.0.2-5
After saving that .htacess file the upgrade-process within my webbrowser was successful without any hassle.