IF() has three arguments:

=IF(<condition, <true branch, <false branch)

You don't say what you expect TRUE to do, but you may want:

=IF(ISTEXT(C3), FALSE, SUM(F1:F20))

Which if the condition is true (i.e, ISTEXT(C3) returns TRUE), the IF()
function returns FALSE.

If, OTOH, ISTEXT(C3) returns FALSE (e.g., C3 is numeric), then the value
of the false branch will be returned, or SUM(F1:F20))



In article ,
Finance Guru wrote:

Hi Everyone

Could some one enlighten as toi what is what is wrong with this function
Excel keeps telling me there is an error,and keeps putting an * before the
TRUE
=IF(ISTEXT(c3),FALSE,sum(F1:f20),TRUE)

C3 = 999
F1 : F20 contain various numerical amounts

so if C3 is False,which it is then ???? i stumped
As always
Many thanks to all respondents