If getting this error when running the payroll to-date summary report, copy back a clean SQWGRP8 and 9 frt and frx's - also look to see if the customer has bespoke report layouts setup such as A_WGRP8 or A_WGRP9 and remove these advising bespoking these reports is not advisable as they will not then include any new/removed columns/headings.  The summary this period and to-date should always be left as the standard.