[vba] Show "Open File" Dialog

In Access 2007 you just need to use Application.FileDialog.

Here is the example from the Access documentation:

' Requires reference to Microsoft Office 12.0 Object Library. '
Private Sub cmdFileDialog_Click()
   Dim fDialog As Office.FileDialog
   Dim varFile As Variant

   ' Clear listbox contents. '
   Me.FileList.RowSource = ""

   ' Set up the File Dialog. '
   Set fDialog = Application.FileDialog(msoFileDialogFilePicker)

   With fDialog

      ' Allow user to make multiple selections in dialog box '
      .AllowMultiSelect = True

      ' Set the title of the dialog box. '
      .Title = "Please select one or more files"

      ' Clear out the current filters, and add our own.'
      .Filters.Clear
      .Filters.Add "Access Databases", "*.MDB"
      .Filters.Add "Access Projects", "*.ADP"
      .Filters.Add "All Files", "*.*"

      ' Show the dialog box. If the .Show method returns True, the '
      ' user picked at least one file. If the .Show method returns '
      ' False, the user clicked Cancel. '
      If .Show = True Then

         'Loop through each file selected and add it to our list box. '
         For Each varFile In .SelectedItems
            Me.FileList.AddItem varFile
         Next

      Else
         MsgBox "You clicked Cancel in the file dialog box."
      End If
   End With
End Sub

As the sample says, just make sure you have a reference to the Microsoft Access 12.0 Object Library (under the VBE IDE > Tools > References menu).