You have to be careful where you upload the files, there is a file hierarchy that must be maintained.
it goes like this domain_name -> htdocs -> index.html
The starting file has to always be index.html the first folder has to be the domain name address example gametest.byethost7.com and inside it there has to be folder called htdocs.
Also in the root directory you have to have folder called logs, if you delete any of those or rename them it wont work.
I am not using their online manager to upload files, instead I am using filezila to directly connected to the ftp server they provide you, and I upload the files there.
Here is a screenshot of my test server folders. You should set yours the same, with different names of course.