expired security certificate

I renewed our site certificate security Thursday that was
set to
expired today.  It did not get renewed & now Windows
issues an expired
security warning and Google Checkout won't process orders. 
Is there
anything that can be done about this in the meantime while
we
temporarily switch to shared SSL while we wait to find out
why it's not
renewed--as far as Google Checkout is concerned?

I got an e-mail from Google informing me of the problem, but
I don't
know how to let them know it's fixed, I don't know where the
orders
went that they show as being processed, etc.