Help removing duplicate VBA projects

Well, good news, bad news. That did clear the extra copies. I hibernate my computer every night so I was due for a restart. Unfortunately that didn't fix the problem I was having with my macro not doing what it's supposed to do. I was given this coding:

Private Sub Workbook_Open()
    Dim mrng As Range
    Dim res As Variant
    Dim ws As String
    
    On Error Resume Next
    Application.Goto Reference:=Worksheets("SUMMARY").Range("A1"), _
       Scroll:=True
    If Err = 9 Then  'actually is subscript out of range
        MsgBox "Requested worksheet ""SUMMARY"" was not found " _
          & "by Workbook_Open in ThisWorkbook."
    End If
    
    Set mrng = Range("A1:ZZ1")
    mdate = Int(Now())
    res = Application.Match(CLng(mdate), mrng, 1)
    
    ws = UCase(Cells(2, res))
    If WorksheetExists(ws) Then
            MsgBox "Worksheet " & ws & " already exists", vbExclamation, "Error"
            Exit Sub
    Else
    

    Sheets("MASTER").Copy Before:=Sheets("SUMMARY")
    ActiveSheet.Name = ws
    ActiveSheet.Rows("1:1").ClearContents
    
    End If


    On Error GoTo 0     'only needed if you have more code
End Sub
Function WorksheetExists(WSName As String) As Boolean
On Error Resume Next
WorksheetExists = Worksheets(WSName).Name = WSName
On Error GoTo 0
End Function

It works on 2 of my files but not the other 2. Any idea why this wouldn't have added a new worksheet for this week? It worked previously and has added one or two worksheets since creating the workbook.

Thanks again!

Post deleted.