Await 要求类型 Task 有合适的 GetAwaiter 方法

我只是将我的工作应用程序从 4.6.1 移至框架 4.0，我遇到了唯一的一个问题。我收到的错误消息如主题所示。我还有第二个错误：

SendPingAsync is not a member of 'Ping'

主题错误出现在该行突出显示的以下方法中：

Await IsDestinationReachable(IPAddress)

Method:

 Public Async Sub Pinguj(sender As Object, e As EventArgs)
        Dim isReachable As Boolean = Await IsDestinationReachable(IPAddress)
        ListBox2.Items.Add("a teraz zmiana")
        If isReachable Then
            tsPingResultIcon.BackColor = Color.Green
        Else
            tsPingResultIcon.BackColor = Color.Red
        End If
    End Sub

第二个错误出现在这一行的以下方法中：

pinger.SendPingAsync(hostnameOrAddress)

method:

 Public Async Function IsDestinationReachable(ByVal hostnameOrAddress As String) As Task(Of Boolean)
        Dim reachable As Boolean = False
        Try
            If My.Computer.Network.IsAvailable Then
                Dim pinger As Ping = New Ping()
                Dim result As PingReply = Await pinger.SendPingAsync(hostnameOrAddress)
                reachable = result.Status = IPStatus.Success
            End If
        Catch pingException As System.Net.NetworkInformation.PingException
        Catch genericNetworkException As System.Net.NetworkInformation.NetworkInformationException
            ' Fail silently and return false
        End Try
        Return reachable
    End Function