Bertorox the correct way is to do the following.... I just solved mine.....
<html>
<title>UNDER CONSTRUCTION</title>
<br>
<body>
<center>
<applet code=Game.class codebase=dev/SUPINC/ name=Game
width="1024" height="768">
<param name="bgcolor" value="ffffff">
<param name="fontcolor" value="000000">
Your browser is not Java enabled.
</applet>
</center>
</body>
</html>
Now my index.html file is in the root of my webhost ..... the Game.class is @ /dev/SUPINC/ so I used (codebase=dev/SUPINC/) to navigate to that directory to tell the page that's where my Game.class file is located.....
ALSO VERY IMPORTANT!!! Make sure when you upload your items there'll be a file called (IN MY EXAMPLE) Game.class AND a file called Game$1.class
YOU MUST UPLOAD THEM BOTH!
That fixed my error
You can see mine in action here:
UNDER CONSTRUCTION