Magento different onepage checkout first step (2 variants)

Question

we noticed the strangest thing. Sometimes it seems like Magento 'forgets' the checkout as guest option ... (that I am sure of that is active, because it always is)

However, sometimes we only see 1 option (instead of 2) : the only button available is create an account

Is there something logical that I am missing?

And the strange thing is that the setting is enable guest checkout = yes

Answer 1

Goto adminpanel then.

system > configuration > checkout

In Checkout options

Enable Allow Guest Enable