If you can access the directory from Windows File Explorer then yes. Call the following function from your macro to write the name of the file in your document. Test it with the test macro and the folder in question.
Code:
Option Explicit
Sub Test()
MsgBox LatestFile("C:\Path") 'The path you want to test
End Sub
Function LatestFile(strPath As String) As String
Dim oFS As Object
Dim strFile As String
Dim strFilename As String
Dim dDate As Date
Do Until Right(strPath, 1) = Chr(92)
strPath = strPath & Chr(92)
Loop
Set oFS = CreateObject("Scripting.FileSystemObject")
dDate = "01/01/1900"
strFile = Dir$(strPath & "*.*")
While strFile <> ""
If oFS.GetFile(strPath & strFile).DateLastModified > dDate Then
strFilename = strPath & strFile
dDate = oFS.GetFile(strPath & strFile).DateLastModified
End If
strFile = Dir$()
Wend
LatestFile = strFilename
lbl_Exit:
Set oFS = Nothing
Exit Function
err_Handler:
LatestFile = ""
Err.Clear
GoTo lbl_Exit
End Function