Compile error on Excel 2010, but not on Excel 2003

Question

I can't explain what is wrong with this simple code. It works perfectly on Excel 2003, but in Excel 2010 it displays:

Compile error: Sub of Function not defined.

Can anyone explain why is there an error on Excel 2010?

Sub Test_File_Opened()
    If IsFileOpen("D:\Test.xls") Then
        MsgBox "File is open!"
    Else
        MsgBox "File is closed!"
    End If
End Sub

Answer 1

The IsFileOpen function is not present in your code, this is the only possible explanation. You must declare it somewhere in your VBA module.

Here are a couple of things to check :

• Did you misspell the procedure name?
• Try to call a procedure from another project without explicitly adding a reference to that project in the References dialog box.
• Specify a procedure that is not visible to the calling procedure.
• Declare a Windows dynamic-link library (DLL) routine or Macintosh code-resource routine that is not in the specified library or code resource.

Answer 2

IsFileOpen is not a VBA built-in function. It probably comes from this Microsoft page (as pointed out by rusk in a comment) and the code just has to be made available in your new Excel 2010 workbook eg pasted into a module.

Why was it available in your Excel 2003 workbook but in your 2010 workbook? Could be any of a range of things. It's in another module the you didn't copy over to the new workbook. It's in an add-in not made available in your current installation of Excel 2010. Etc. Etc. You don't give enough information to diagnose the problem properly, but the remedy is the same regardless, as indicated above.