Option Explicit
Sub OpentxtSheets()
Const sPath = "D:\Tests\" 'Change to suit
Dim sFil As String
Dim owb As Workbook
Dim sh As Worksheet
Set sh = Sheet1 'Change to suit
sFil = Dir(sPath & "*.txt") 'Note it opens txt format
Do While sFil <> ""
Set owb = Workbooks.Open(sPath & sFil)
Range("A1").CurrentRegion.Copy sh.Range("A65536").End(xlUp)(2)
owb.Close False 'Close don't save
sFil = Dir
Loop
End Sub