Copying data from other workbooks and pasting into master workbook

OK so I have tried everything I can think of to modify this macro I pulled from the net but I keep getting errors. I don’t know where I am going wrong in addition to my limited knowledge of coding macros has really put me in a bind. I need this macro to prompt me to select a workbook(s) then copy everything on Sheet2 to my master workbook until all of the source workbooks have been processed into the master.

Here is my code. I have reverted it back to the original I copied from the net because I butchered the original too much.
I have also included my sample data.

Sub Collect_Data()

  Dim C As Long
  Dim DstWks1 As Worksheet
  Dim DstWks2 As Worksheet
  Dim LastRow As Long
  Dim R As Long
  Dim SrcWkb As Workbook
  Dim StartRow As Long
  Dim wkbname As Variant
  Dim xlsFiles As Variant

  
   'Starting column and row for the destination workbook
    C = 1
    R = 1
   'Set references to destination workbook worksheet objects
    Set DstWks1 = ThisWorkbook.Worksheets("Sheet1")
    Set DstWks2 = ThisWorkbook.Worksheets("Sheet2")
    
   'Starting row on source worksheet
    StartRow = 1
    
   'Get the workbooks to open GetOpenFilename
    xlsFiles = Application.FileDialog(FileFilter:="Excel files (*.xls*),*.xls*", MultiSelect:=True) 'Excel files (*.xls),
    Application.AskToUpdateLinks = False
      If VarType(xlsFiles) = vbBoolean Then Exit Sub
      
     'Loop through each workbook and copy the data to this workbook
      For Each wkbname In xlsFiles
        Set SrcWkb = Workbooks.Open(Filename:=wkbname, ReadOnly:=True)
          LastRow = SrcWkb.Worksheets(2).Cells(Rows.Count, "AB").End(xlUp).Row
            Cells(Rows.Count, "AD").Select
            Selection.Copy
            If LastRow >= StartRow Then
              With SrcWkb.Worksheets(2)
                DstWks1.Cells(R, C).Resize(LastRow - StartRow + 1, 1).Value = _
                .Range(.Cells(StartRow, "AD"), .Cells(LastRow, "AD")).Value
                Sheets(1).Select
                ActiveSheet.Paste
              End With
            End If
          LastRow = SrcWkb.Worksheets(1).Cells(Rows.Count, "AD").End(xlUp).Row
            If LastRow >= StartRow Then
              With SrcWkb.Worksheets(1)
                DstWks2.Cells(R, C).Resize(LastRow - StartRow + 1, 1).Value = _
                .Range(.Cells(StartRow, "AD"), .Cells(LastRow, "AD")).Value
              End With
            End If
        C = C + 1
        SrcWkb.Close SaveChanges:=False
        ''SrcWkb.Close''
      Next wkbname
      
End Sub

UNSPSC_v14_0801.xlsUNSPSC_v15_1101.xlsMaster.xlsx

Nope not error, The macro sems to let me select the file, then the screen flashes, and the macro ends. It never goes past this line:
I got it past this line once but it thew an out of range error. Sorry I didnt make note of the actual error code.

xlsFiles = Application.GetOpenFilename(FileFilter:="Excel files (*.xls*),*.xls*", MultiSelect:=True) 'Excel files (*.xls),

First correction

 xlsFiles = Application.GetOpenFilename(FileFilter:="Excel files (*.xls*),*.xls*", MultiSelect:=True) 'Excel files (*.xls),

@ AB33 - Both my original line and yours seemed function properly but nothing actual goes anywhere after that. Just terminates the macro.

I meant A through D. Dang it. ok so I placed a : between all the ranges and I now get a Run-Time Error 1004 at this line:
LastRow = SrcWkb.Worksheets(2).Cells(Rows.Count, "A:D").End(xlUp).Row

The sheet names in the master file are Sheet1, Sheet2, Sheet3 but the source file names are custom per tab. I want everything off of tab two Columns A:D. Which parts of the code do you feel is unnecessary? My coding experience is REALLY rusty.

  LastRow = SrcWkb.Worksheets(2).Cells(Rows.Count, "A").End(xlUp).Row

OR

 LastRow = SrcWkb.Worksheets(2).Cells(Rows.Count, "D").End(xlUp).Row

I will be off site until tomorrow.

Lastrow Should be "D". Here is what I have now and it does run through the sheets but it doesnot paste the values in the master fille.

Sub Collect_Data()

  Dim C As Long
  Dim DstWks1 As Worksheet
  Dim DstWks2 As Worksheet
  Dim LastRow As Long
  Dim R As Long
  Dim SrcWkb As Workbook
  Dim StartRow As Long
  Dim wkbname As Variant
  Dim xlsFiles As Variant

  
   'Starting column and row for the destination workbook
    C = 1
    R = 1
   'Set references to destination workbook worksheet objects
    Set DstWks1 = ThisWorkbook.Worksheets("Sheet1")
    Set DstWks2 = ThisWorkbook.Worksheets("Sheet2")
    
   'Starting row on source worksheet
    StartRow = 1
    
   'Get the workbooks to open GetOpenFilename
    'xlsFiles = Application.FileDialog(FileFilter:="Excel files (*.xls*),*.xls*", MultiSelect:=True) 'Excel files (*.xls),
    xlsFiles = Application.GetOpenFilename(FileFilter:="Excel files (*.xls*),*.xls*", MultiSelect:=True) 'Excel files (*.xls),
    Application.AskToUpdateLinks = False
      If VarType(xlsFiles) = vbBoolean Then Exit Sub
      
     'Loop through each workbook and copy the data to this workbook
      For Each wkbname In xlsFiles
        Set SrcWkb = Workbooks.Open(Filename:=wkbname, ReadOnly:=True)
          LastRow = SrcWkb.Worksheets(2).Cells(Rows.Count, "D").End(xlUp).Row
            Cells(Rows.Count, "D").Select
            Selection.Copy
            If LastRow >= StartRow Then
              With SrcWkb.Worksheets(2)
                DstWks1.Cells(R, C).Resize(LastRow - StartRow + 1, 1).Value = _
                .Range(.Cells(StartRow, "A"), .Cells(LastRow, "D")).Value
                Sheets(1).Select
                ActiveSheet.Paste
              End With
            End If
          LastRow = SrcWkb.Worksheets(1).Cells(Rows.Count, "D").End(xlUp).Row
            If LastRow >= StartRow Then
              With SrcWkb.Worksheets(1)
                DstWks2.Cells(R, C).Resize(LastRow - StartRow + 1, 1).Value = _
                .Range(.Cells(StartRow, "A"), .Cells(LastRow, "D")).Value
              End With
            End If
        C = C + 1
        SrcWkb.Close SaveChanges:=False
        ''SrcWkb.Close''
      Next wkbname
      
End Sub

This is my guess work on what you are trying to do.
You should have master book with sheet1 as a destination sheet. Sheet1 has also a header.

Sub Collect_Data()

  Dim DstWks1 As Worksheet, DstWks2 As Worksheet, LastRow As Long, NR As Long, SrcWkb As Workbook, StartRow As Long
  Dim wkbname As Variant
  Dim xlsFiles As Variant
  Application.ScreenUpdating = 0

   'Set references to destination workbook worksheet objects
    Set DstWks1 = ThisWorkbook.Worksheets("Sheet1")
    Set DstWks2 = ThisWorkbook.Worksheets("Sheet2")

   'Starting row on source worksheet
    StartRow = 1
    
   'Get the workbooks to open GetOpenFilename
   
    xlsFiles = Application.GetOpenFilename(FileFilter:="Excel files (*.xls*),*.xls*", MultiSelect:=True) 'Excel files (*.xls),
    Application.AskToUpdateLinks = False
      If VarType(xlsFiles) = vbBoolean Then Exit Sub
      
     'Loop through each workbook and copy the data to this workbook
      For Each wkbname In xlsFiles
        Set SrcWkb = Workbooks.Open(fileName:=wkbname, ReadOnly:=True)
        With SrcWkb.Worksheets(2)
            LastRow = .Cells(.Rows.Count, "D").End(xlUp).Row
            .Range("A2:D" & LastRow).Copy
            NR = DstWks1.Cells.Find("*", , , , xlByRows, xlPrevious).Row + 1
            DstWks1.Range("A" & NR).PasteSpecial xlValues
        End With
         Application.ScreenUpdating = True
        SrcWkb.Close SaveChanges:=False
        ''SrcWkb.Close''
      Next wkbname
      
End Sub

AB33 - Thats exactly what i am looking for. Thank your for your help. You are a life saver!