I did remove all the One page checkout files from the server after the site broke.

Now I can only get to step 1 of checkout and then when I click checkout it goes back to the main page. The goods stay in the cart and if I ;ogin and out thay stay there. I don't know what has happened to cause this issue.

Any help would be appreciated as I am pulling my hair out trying to work out what I must have done wrong.