"Reference is not Valid" when calling fast fourier transform

[JacksonRJones]

Hello. I get the message "Reference is not Valid" when the following piece
of code executes from my program; k is an integer, focallength is a double,
and sheetname is a string:

sheetname = "r32-" & k + 1 & "-" & FocalLength

Dim infourierrng As Range
Dim outfourierrng As Range

Set infourierrng = Worksheets(sheetname).Range("J15:J1038")
Set outfourierrng = Worksheets(sheetname).Range("L15:L1038")

Application.Run "ATPVBAEN.XLA!Fourier", infourierrng, outfourierrng, False,
False

This message appears in a messagebox; if I click OK, everything proceeds
fine, and the fourier transform works, so it isn't really much of a problem,
except I don't want this message to appear anytime anyone runs this macro.
Any help would be greatly appreciated.

 

[K Dales]

Seems like the issue occurs somewhere within the external procedure
"ATPVBAEN.XLA!Fourier. Without knowing the code behind that procedure there
is no way to know why the messagebox appears or how to prevent it.

 

[JacksonRJones]

ATPVBAEN.XLA!Fourier is part of the standard analysis toolpack that comes
with with excel 2003. It can be accessed from the tools->data analysis menu
in excel. I think the problem has something to do with using the sheetname
as a variable, because I did not get this error message when I was just using
"sheet1" in place of the variable sheetname. Anyways, maybe this will help
someone figure out what the problem is. Thanks.

 

[JacksonRJones]

In case anyone reads this, I ended up fixing this problem by activating the
worksheet which had the data I wanted to do the fft on and then defining the
range for the active worksheet, then referring this range for the fft:

Worksheets(sheetname).Activate

Set infourierrng = Range("J15:J1038")
Set outfourierrng = Range("L15:L1038")

Application.Run "ATPVBAEN.XLA!Fourier", infourierrng, outfourierrng, False,
False