You possibly have Temp defined elsewhere in the module as a constant with a
numerical value. In your original workbook, that is.

"Dave F" wrote:

This is interesting. I copied the code below, inserted it into a
module in a completely new workbook, entered the function, and there
was no error!

Wonder what could have caused the error in the original workbook?

On Nov 2, 7:39 pm, Dave F wrote:
The following UDF gives a type 13 error when using XL 2007:

Function SetTemp1(Temp, Temp1)
Dim ss As String
If Temp = Temp1 Then ' Constant not a number
SetTemp1 = Temp
ElseIf Val(Temp) = Temp1 Then 'constant number
SetTemp1 = Temp1 * 2
Else ' Formula
ss = Temp
If Left(ss, 1) = "=" Then ss = Right(ss, Len(ss) - 1)
SetTemp1 = "=(" & ss & ")*2"
End If
End Function

The debugger highlights If Temp = Temp1 Then ' Constant not a
number
as causing the error.

I received this workbook from someone else, so I'm not too clear on
what this UDF is supposed to do or what is causing the error.

Thoughts?

Dave