Where do you get syntax error? In T-SQL it's NULL (w/o '.').
You don't need to check for tapcomp.fdate > ctod("12/31/9999") and you can use date literal instead of CTOD()

tapcomp.fdate < {^1753/01/01}

>
>But for some reason I am getting the syntax error. Here is my code:
>
>

>IF empty(tapcomp.fdate) or tapcomp.fdate < ctod("01/01/1753") or ;
>   tapcomp.fdate > ctod("12/31/9999")
>   lFdate = ".NULL."
>ELSE
>   lFdate = DTOC(tapcomp.fdate)
>ENDIF
>

>
>Do you see anything that I might be missing?
>
>Thank you.