Using VB Code I attached this to a button:
Private Sub btnOpen_Click()
Me.btnOpen.HyperlinkAddress = "C:\Folder\Files\File.xls"
End Sub
You could also just have the HyperlinkAddress automatically on the button, this is edited code... in the actual database the user filled in the folder path and filename into a textbox and had this button open it. the code was:
Private Sub btnOpen_Click()
Dim file As String
If Not IsNull(FileName) Then
file = FileName
Me.btnOpen.HyperlinkAddress = "C:\Files\" & file
Else
Me.btnOpen.HyperlinkAddress = ""
End If
End Sub