Function Name Can't be Same as Module Name

In the versions of Microsoft Excel listed above, if you attempt to run a function that has the same name as a Visual Basic module, and the Visual Basic module is located in the same workbook as the function, you may receive one of the following error messages:

Instead of creating a function, create a Sub procedure. A Sub procedure can have the same name as a module without causing an error.

Note that Sub procedures cannot be called from worksheet formulas.

Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements. You may receive an error message if you run a function called "Test1" if that function is located in a Visual Basic module in a workbook that also contains a module named "Test1".

Example

1. In a new workbook, insert a new Visual Basic module and name it Test1.
2. In Test1 (the module that you just inserted), type the following function:

         Function Test1()
             TestVar = 1
         End Function
   						

3. In cell A1 of a new worksheet in the same workbook, type the following formula:
   =Test1()
   You may receive the error message "Expected procedure, not module". A #NAME! error value is returned to cell A1.
4. In cell A1 of a new worksheet in a different workbook, enter the formula:
   =Book1!Test1()
   You may receive an error message. A #NAME! error value appears in cell A1.