Boa tarde!!

Public Sub Teste()
    Dim Shell As Object
    Dim IE As Object
 
    Set Shell = CreateObject("Shell.Application")
 
    For Each IE In Shell.Windows
        If TypeName(IE.Document) = "HTMLDocument" Then
            IE.Quit
        End If
    Next
End Sub

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Sub Teste2()
    Dim objWMI As Object, objProcess As Object, objProcesses As Object
    Set objWMI = GetObject("winmgmts://.")
    Set objProcesses = objWMI.ExecQuery( _
        "SELECT * FROM Win32_Process WHERE Name = 'iexplore.exe'")
    For Each objProcess In objProcesses
        Call objProcess.Terminate
    Next
    Set objProcesses = Nothing: Set objWMI = Nothing
End Sub

Att