"The underlying object does not exist" with MSIEXEC

I do not know how to map this property.

I'll reformulate my question, in my code has a line of code that the TestComplete does not recognize,ie, getting lost.

 Below is my Code. In Points "underline"  o TesComplete not is recognizing my Code or not  can map the property correct of applying.  

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Sub InstalacaoFPw '''''' Não esta Funcionando Corretamente

Dim FrmLGInstalador, FrmLGInstalador1, FrmLGInstalador2, FrmLGInstalador3, FrmLGInstalador4

Dim BtnAvancar, BtnAvancar1, BtnCancelar, BtnSim, BtnNao, TpSelecao

Call TestedApps.Instala__o_FPw.Run(1, True)

Delay(2000)

Set FrmLGInstalador = Aliases.LGInstalador1.wndWindowsForms10Window8app011c7a8c

Set FrmLGInstalador1 = Aliases.LGInstalador.wndWindowsForms10Window8app033c0d9d.WindowsForms10SysTabControl32app033c0d9d

Set FrmLGInstalador2 = Aliases.LGInstalador1.wndWindowsForms10Window8app033c0d9d

Set FrmLGInstalador3 = Aliases.LGInstalador1.wndWindowsForms10Window8app011c7a8c.WindowsForms10SysTabControl32app011c7a8c.tpSelecao.WindowsForms10ToolbarWindow32app011c7a8c

Set FrmLGInstalador4 = Aliases.msiexec.wndMsiDialogCloseClass '''' Formulario que nao Funciona

Set BtnAvancar = FrmLGInstalador.btnAvan_ar

Set BtnCancelar = FrmLGInstalador2.btnCancelar

Set BtnAvancar1 = FrmLGInstalador4.btnAvan_ar

Set BtnSim = Aliases.LGInstalador1.dlgLGInstalador.btnSim

Set TpSelecao = FrmLGInstalador3

If BtnAvancar.Enabled Then

BtnAvancar.ClickButton

Log.Message("Botão 'Avançar'")

Else

Log.Message("Botão 'Cancelar'")

BtnCancelar.ClickButton

BtnSim.ClickButton

End If

Call TpSelecao.ClickItem("Todos", False)

BtnAvancar.ClickButton

'''' Formulario que nao Funciona

BtnAvancar1.ClickButton



End Sub

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 What should I do.

 Thanks.