Good afternoon,
I seem to be having a similar problem to the one reported at: http://community.quickfile.co.uk/t/pay-online-not-working-on-mapped-invoices/8611
Same client, this time when he clicks 'Pay Online' on his QF mapped invoice it takes him to the dashboard.
Once again I have left the invoice (10814) unpaid, to allow for troubleshooting.
Let me know if you need any further details.