I understand that multiple threads of this question has already been posted by me. They contain wrong information and I have asked for them to be deleted.

Problem: I have a Workbook containing two worksheets "X" and "FILES". The worksheet "FILES" contains the name of each file in a directory on my desktop "C:\Users\Owner\Desktop\DATA-X" in cells (A1:A1000) (There are 1000 files in the folder "DATA-X". The worksheet "X" is a blank worksheet.

The following code loops 1000 times, each time importing the "k"th file from the folder "DATA-X" and storing it in the worksheet "X". After each loop, the worksheet "X" gets replaced with the data in the next file from the folder "DATA-X". As the program is running, it can be seen in the task manager that memory is accumulating in the Excel program. In fact, it cannot finish because it will use up all memory by then (I get a message "OUT OF MEMORY"). Why is this memory leak occuring and how can I fix this? Any help would be greatful. 

Sub MemoryTest()
 
    Dim qt As QueryTable
    Dim WSh As Worksheet

    Sheets("X").Select
    
    For k = 1 To 1000
    
    Cells.Select
    Selection.Delete Shift:=xlUp
    
    Range("A1").Select
    With ActiveSheet.QueryTables.Add(Connection:= _
        "TEXT;" & "C:\Users\Owner\Desktop\DATA-X" & "\" & Sheets("FILES").Cells(k, 1).Value _
        , Destination:=Range("$A$1"))
        .Name = Sheets("FILES").Cells(k, 1)
        .FieldNames = True
        .RowNumbers = False
        .FillAdjacentFormulas = False
        .PreserveFormatting = True
        .RefreshOnFileOpen = False
        .RefreshStyle = xlInsertDeleteCells
        .SavePassword = False
        .SaveData = True
        .AdjustColumnWidth = True
        .RefreshPeriod = 0
        .TextFilePromptOnRefresh = False
        .TextFilePlatform = 437
        .TextFileStartRow = 1
        .TextFileParseType = xlDelimited
        .TextFileTextQualifier = xlTextQualifierDoubleQuote
        .TextFileConsecutiveDelimiter = False
        .TextFileTabDelimiter = False
        .TextFileSemicolonDelimiter = False
        .TextFileCommaDelimiter = False
        .TextFileSpaceDelimiter = False
        .TextFileColumnDataTypes = Array(1)
        .TextFileTrailingMinusNumbers = True
        .Refresh BackgroundQuery:=False
    End With
    Range("A1").Select
    Selection.TextToColumns Destination:=Range("A1"), DataType:=xlFixedWidth, _
        FieldInfo:=Array(0, 1), TrailingMinusNumbers:=True

     For Each WSh In ThisWorkbook.Worksheets
          For Each qt In WSh.QueryTables
               qt.ResultRange.ClearContents
               qt.Delete
          Next qt
     Next WSh
     
    Do Until ActiveWorkbook.Connections.Count = 0
        ActiveWorkbook.Connections(ActiveWorkbook.Connections.Count).Delete
    Loop
    
     Next k
     
End Sub