Sub MergeSheets()
Dim SrcBook As Workbook
Dim fso As Object, f As Object, ff As Object, f1 As Object
Application.ScreenUpdating = False
Set fso = CreateObject("Scripting.FileSystemObject")
Set f = fso.GetFolder[COLOR="red"]("C:\Folder Path")[/COLOR] Set ff = f.Files
For Each f1 In ff
Set SrcBook = Workbooks.Open(f1)
Range("A1:M" & Range("A65536").End(xlUp).Row).Copy
ThisWorkbook.Worksheets(1).Activate
Range("A65536").End(xlUp).Offset(1, 0).PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks _
:=False, Transpose:=False
Application.CutCopyMode = False
SrcBook.Close
Next
End Sub