Problem with checkout module

[[abs]]

Hi guys,

 

I have just installed oscommerce in my hosting and I'm getting started. I have been making tests and everything is AOK, excepting one problem.

 

I add products to the shophing cart, and when I go in, it's ok. But when I click on Checkout a 404 error 'page not found' is displayed on my explorer. What's this problem about? How Do I repair this?

 

The site is: www.loterialafortuna.net <- Please take a look and tell me

 

Thanks!

[[abs]]

Does anybody know what is the problem???