I've been looking for this for while, and sharing is carying !

So there is the code I figured from few samples on net. Hope this will help someone !

Code:
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim groupName As String = InputBox("enter group name")
        Try
            If ListView1.FindItemWithText(groupName).Text = groupName Then
                MsgBox(groupName & " already exists")
            Else
                ListView1.Items.Add(groupName)
            End If
        Catch

            ListView1.Items.Add(groupName)
        End Try
    End Sub