Replace Fill Down, Complicated Equation

A) you didn't have the sub named and you had End and not End Sub
B) in the attached workbook I have taken out your modules and commented out the code in ThisWorkbook
C) in the sheets you didn't have anything in Column B and so the code wouldn't fill in anything
D) the code in ThisWorkbook definitely stops the code running
E) the code runs with your codes removed /commented out
F) afraid I don't have the time to plough through your codes to work out what is interfering with the code or not