Invoices sent out this month would not allow the customer to click on the View and Pay Invoice button. A popup instructs them to:
Open the original email you received about this invoice.
Right-click (or control-click) the View Invoice Now button.
From the menu, choose to copy the link address.
Open a new browser tab or window and paste the link.

CLICKING THE LINK HAS BEEN WORKING FOR A LONG TIME. IS THIS A PROBLEM WITH QB OR A NEW "FEATURE" YOU HAVE INTRODUCED.