Help checkout stopped working!

hi I have a shopping cart which has been working fine for the last few months. Then yesterday it has just stopped working for no apparent reason!

after selecting your payment method when you click continue the site goes to the checkout confirmation page but it is empty. My template and enu still appear but there is no content in the page so you can't complete your order.

I havent done any work on this site in the last two weeks so I can't think what has caused this.

Does anyone have any ideas why the checkout confirmation page is empty? Are there any values it needs passing to it I can check etc

any help greatfully received as I am at a loss!

Thanks

Rachael

Does your footer show?

What version of Zen Cart are you using?

Has your webhost upgraded your PHP or MySQL recently?

Are you getting your confirmation emails?
Look at your define_checkout_success.php in Define Pages Editor, is there any content there?

JOhn ><>