Your server seems to be working (I was able to see the readme.html file very quickly), so I would guess it has to do with your wordpress install
We need some more information.
Is this a one-click install you did you manually install it? Is it a brand new install or has it been working for a while.
If it just started happening, have you installed any plugins/made any changes to the site (messed with permalinks, undated files, etc)