The installation can not be completed: You cannot install more than one script in the root directory of a domain."

I got the Wordpress installed but I'm not sure if there are repercussions from my method.
From my research the problem seems to be a fantistico file named "installed_in_root.php".
I found this rather radical fix by deleting the file from a folder named ".fantasticodata".
Because I suspect possible repercussions I saved the file before deleting it.

This is the suggested fix.
1. login to your ftp
2. find folder .fantasticodata
3. find file installed_in_root.php and delete it.