What are you doing exactly, and what error message are you getting? You can publish online games here by picking HTML under "Kind of project" and ticking the "This file will be played in the browser" checkbox after uploading the right archive (it has to contain a file called index.html).
Viewing post in Indie game online: recordsland
I was getting an error because I was trying to add an external link (not a file) and I got the message in the page section: "You've configured this page to show a html game but you haven't uploaded the appropriate file!"
Now it is OK - I have followed the steps you suggested and I have put a link to the webpage in my index.html file (that game is not downloadable). It runs well on the browser.