Change of Hosting Provider

Hi,

I have changed my hosting provider for my wordpress site and have migrated the data from my old host across to my new host (fasthosts to 20i). After I have changed provider I cannot create new invoices as the directory it is trying to save the invoice in the directory located the old host rather than the new one. How do I change which directory it tries to save the invoices in so I can send invoices to clients?

Thanks

Nathan