I have been stuck on the first formula for days. When I enter it the error I get is:

I'm not sure what this means, I have gone back and double checked the naming of all of my modules and made sure I was typing the formula correctly:
IF 'SYS09 Version Details'.Forecast? THEN 'EMP02 Employee Expenses'.Headcount[SUM: 'SYS08 Employee Details'.Country] ELSE 'DATA01 P&L Actual and Budget'.Headcount
I've tried typing it, copying it, no matter what I do it won't work. If someone could provide some guidance I would really appreciate it.