When running the Year end I set up the online payslips and uploaded historical payslips for all employees.

We are processing our weekly payroll, when clicking on Upload Online Payslips, there is a notification at the bottom regarding 4 historical leavers, stating their email is invalid.  I have selected the date I want the payslips publishing, but it the button to publish payslips is not available.  IS this because of the error on the historical leavers?  How do I correct this?