Here are two quick functions;

The first getType takes in a path of a folder or file and returns the type.

Function getType(ByRef path As String) As String
    On Error Resume Next
    Dim res As Long
    res = GetAttr(path)
    If Err.Number = 0 Then
        If res And vbDirectory Then
            getType = "folder"
        Else
            getType = "file"
        End If
    Else
        getType = "error"
    End If
End Function

The second function getDate takes in a folder or path and returns the date modified. getDate references getType.

Function getDate(ByRef path As String) As Double
    Select Case getType(path)
        Case "file"
            getDate = CreateObject("scripting.filesystemobject").getfile(path).datelastmodified
        Case "folder"
            getDate = CreateObject("scripting.filesystemobject").getfolder(path).datelastmodified
    End Select
End Function

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