Populate master sheet from feeder sheet

Hello all,

I'm trying to create a master spreadsheet and have 3-4 spreadsheets it pulls information from automatically if possible. I've tried the following with no luck:

Sub LoopThroughDirectory()
Dim MyFile As String
Dim erow
Dim Filepath As String
Filepath = "C:\Users\j\Desktop\Req Tracking"
MyFile = Dir(Filepath)
Do While Len(MyFile) > 0
If MyFile = "zmaster.xlsm" Then
Exit Sub
End If

Workbooks.Open (Filepath & MyFile)
Range("A2:D2").Copy
ActiveWorkbook.Close

erow = Sheet1.Cells(Rows.Count, 1).End(xlUp).Offset(1, 0).Row
ActiveSheet.Paste Destination:=Worksheets("Sheet1").Range(Cells(erow, 1), Cells(erow, 4))

MyFile = Dir
Loop
End Sub

Any help would be greatly appreciated