Hello Mallesh,
This should get you started...
Sub UpdateMaster()
Dim DstRng As Range
Dim DstWkb As Workbook
Dim DstWks As Worksheet
Dim File As Object
Dim Files As Object
Dim Filter As Variant
Dim Folder As Object
Dim oShell As Object
Dim Path As Variant
Dim Rng As Range
Dim RngBeg As Range
Dim RngEnd As Range
Dim SrcWkb As Workbook
Dim SrcWks As Worksheet
Set DstWkb = ThisWorkbook
Set DstWks = DstWkb.Worksheets("Sheet1")
Set DstRng = DstWks.Range("A5:D5")
Path = "E:\"
Set oShell = CreateObject("Shell.Application")
Set Folder = oShell.Namespace(Path)
If Folder Is Nothing Then
MsgBox "The folder """ & Path & """ was Not Found.", vbCritical
Exit Sub
End If
For Each Filter In Array("Outgoing Calls.xlsx", "Incoming Calls.xlsx", "Missed Calls.xlsx")
Select Case UCase(Left(File.Name, 3))
Case Is = "OUT": Set DstRng = Array("Outgoing Calls", "Timing")
Case Is = "INC": Set DstRng = Array("Incoming Calls", "Timing")
Case Is = "MIS": Set DstRng = Array("Missed Calls", "Timing")
End Select
Set DstRng = DstRng.Offset(1, 0)
Set Files = Folder.Items
Files.Filter 64, Filter
For Each File In Files
Set SrcWkb = Workbooks.Open(File.Path)
Set SrcWks = SrcWkb.Worksheets("Sheet1")
Set RngBeg = SrcWks.Range("A2:B2")
Set Rng = RngBeg
Set RngEnd = SrcWks.Cells(Rows.Count, "A").End(xlUp)
If RngEnd.Row > RngBeg.Row Then Set Rng = SrcWks.Range(RngBeg, RngEnd)
Rng.Copy DstRng
Set DstRng = DstRng.Offset(Files.Count, 0)
SrcWkb.Close SaveChanges:=False
Next File
Next Filter
End Sub