Loop breaks at different points

Hi,

I have a sheet named SymbolList in which I list stock symbols in the first column, and have row headings in the first row. I use the following sub to get stock quotes from yahoo. I developed a loop that works in steps of 200 because yahoo has a limit of 200 stock symbols that can be acquired in each request. The loop should go through the whole list in loops of 200 until the last row or if by mistake there is an empty row. The problem I face is that the loop does not work in a consistent manner, for example if I use 200 as the step limit, the sub skips all loops and only gets the last one, if I use a limit of 100 the sub skips the first loop and then proceeds, it only works well at a limit of 50.

I hope someone can help me figure out what is wrong with my loop.

Sub UpdateQuotes()
  
    Dim WSW As Worksheet
    Dim Qt As QueryTable
    Dim ConnectionString As String, StockFlags As String
    Dim i As Integer, iLoopLimit As Integer, LastRow As Integer
    
           
    StockFlags = "&f=" + "d1t1l1ve1"
    
        
    DisableUpdate
    
        
    Set WSW = Worksheets("SymbolList")
    
       
    LastRow = Range("A65536").End(xlUp).Row
    
    
    For iLoopLimit = 0 To LastRow Step 200
    
        
        ConnectionString = "URL;http://download.finance.yahoo.com/d/quotes.csv?s="
        i = iLoopLimit + 2
        ConnectionString = ConnectionString + Trim(SymbolList.Cells(i, 1).Text)
        'i = i + 1

        For i = (iLoopLimit + 3) To (iLoopLimit + 51) Step 1
          If Cells(i, 1).Text = "" Then
            Exit For
          Else
            ConnectionString = ConnectionString + "+" + Trim(SymbolList.Cells(i, 1).Text)
          End If
        Next i
       
        
        ConnectionString = ConnectionString + StockFlags
           
        
        
        Set Qt = WSW.QueryTables.Add(Connection:=ConnectionString, Destination:=WSW.Range("H2"))
        
            With Qt
                .FieldNames = True
                .RowNumbers = False
                .FillAdjacentFormulas = False
                .PreserveFormatting = True
                .RefreshOnFileOpen = False
                .BackgroundQuery = True
                .RefreshStyle = xlInsertDeleteCells
                .SavePassword = False
                .SaveData = True
                .AdjustColumnWidth = True
                .RefreshPeriod = 0
                .WebSelectionType = xlSpecifiedTables
                .WebFormatting = xlWebFormattingNone
                .WebPreFormattedTextToColumns = True
                .WebConsecutiveDelimitersAsOne = True
                .WebSingleBlockTextImport = False
                .WebDisableDateRecognition = False
                .WebDisableRedirections = False
                .TablesOnlyFromHTML = False
            End With
 
            With Application
                On Error Resume Next
                Qt.Refresh BackgroundQuery:=False
            End With
 
            WSW.Range("H2:H200").Select
            Selection.TextToColumns Destination:=WSW.Range("H2"), DataType:=xlDelimited, _
                TextQualifier:=xlDoubleQuote, ConsecutiveDelimiter:=False, Tab:=True, _
                Semicolon:=False, Comma:=True, Space:=False, Other:=False, FieldInfo _
                :=Array(Array(1, 1), Array(2, 1), Array(3, 1), Array(4, 1), Array(5, 1))
 
            WSW.Range("H2:M200").Select
            Selection.Copy
            SymbolList.Cells(iLoopLimit + 2, 2).Select
            Selection.PasteSpecial Paste:=xlValues, Operation:=xlNone, SkipBlanks:=False, Transpose:=False
 
            
    Next iLoopLimit
    
  
    
    EnableUpdate
    
       
End Sub