Weeknum Add In doesn't load when launching Excel

[Eugene]

I am using Excel XP and have a spreadsheet template in which in use
the WEEKNUM function. Via the Tools - Add-Ins menu I have placed a
checkmark for the "Analysis ToolPak" and "Analysis ToolPak - VBA"
Add-In. The formula says =IF(A11;WEEKNUM(A11;1);"") to determine the
week number, based on the date entered in cell A11. It works fine. So
far, so good. However, when I close Excel, restart it, open a new
document based upon the template and enter a (valid) date in cell A11,
the result of the formula is: #NAME?
Looking at the Add-Ins the checkmarks are still in place. When I
uncheck the two ToolPak Add-Ins and recheck them, the formula works
again. The cell with the formula is protected.
Does anyone know how to solve this?

 

[Stephen Bye]

Your template file contains an unknown name called 'WEEKNUM'.
Every time you load the file it will still be an unknown name.
Load the file, uncheck & check the add-ins so that the name is resolved.
Then save the template.
Now it contains a known name 'WEEKNUM' that refers to the analysis tool
pack.