Drupal didn't work out of the box and gave the following white screen of death:
500 Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
After some research I found out that One.com hosting didn't like Drupal's default .htaccess file. I had to disable the following lines to make it work:
# Don't show directory listings for URLs which map to a directory.
Options -Indexes
# Follow symbolic links in this directory.
Options +FollowSymLinks
I also had to disable the following in the .htaccess file in the files directory.
Options None
Options +FollowSymLinks