I have a solution and the function is now working. The error was #NAME?.
The only thing in the formula bar that did not switch to UPPERCASE was the
function "networkdays" telling me that "networkdays" function was the
problem. Turns out the fix was my permissions on my new XP computer.

Thank you for your willingness to help.

"JE McGimpsey" wrote:

First, what do you mean by "not working"? Do you get an error? An
incorrect result?

Is your add-in installed in XL, as well as on your HD (e.g.,
Tools/Add-ins...)

is r3 earlier than u3?

In article ,
"Al H." wrote:

I have been successfully using this function for quite some time. My formula
is (=if(t30,networkdays(r3,u3)," ") where t3 is a date also. Before you
ask, yes, I have the analysis tool pack add-in. The only difference is I
have switched over to the new XP operating system. Any ideas?