Drive Combobox Device Not Ready?

Imports System.IO
Imports System.Collections.ObjectModel
Imports System.ComponentModel
Imports System.Windows.Forms.Form
Imports System

Public Class Form1
    Public Sub New()
        Call InitializeComponent()
        Try
            If LicenseManager.UsageMode <> LicenseUsageMode.Designtime Then
                For Each d As DriveInfo In DriveInfo.GetDrives()
                    If d.IsReady Then                    
                        ComboBox1.Items.Add(d.Name &  d.VolumeLabel) 'never use + to join strings!
                    Else
                        ComboBox1.Items.Add(d.Name)
                    End If
                Next d
                ComboBox1.DrawMode = DrawMode.OwnerDrawFixed
                ComboBox1.DropDownStyle = ComboBoxStyle.DropDownList
        End If
        Catch ex As IO.IOException
            'MsgBox (ex.Message, MsgBoxStyle.Exclamation,"IOException")
        End Try
    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ComboBox1.SelectedIndex = 0
    End Sub

    Private Sub ComboBox1_DrawItem(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) Handles ComboBox1.DrawItem
        If e.Index = -1 Then
            Return
        End If
        Dim drive As DriveInfo = CType(ComboBox1.Items(e.Index), DriveInfo)
        Dim icon As Icon
        Select Case drive.DriveType
            Case (DriveType.Fixed)
                icon = ShellIcons.HardDisk
            Case (DriveType.CDRom)
                icon = ShellIcons.CDROM
            Case (DriveType.Network)
                icon = ShellIcons.NetDisk
            Case (DriveType.Removable)
                icon = ShellIcons.FloppyDisk
            Case Else
                icon = ShellIcons.UnknownDisk
        End Select
        Dim iconbox As New Rectangle(e.Bounds.X, e.Bounds.Y, e.Bounds.Height, e.Bounds.Height)
        e.DrawBackground()
        e.Graphics.DrawIcon(icon, iconbox)
        icon.Dispose()
        Dim text As String = drive.Name
        If drive.IsReady Then
            If drive.VolumeLabel <> "" Then
                text = text & " (" & drive.VolumeLabel & ")"
            End If
        End If
        e.Graphics.DrawString(text, e.Font, New SolidBrush(e.ForeColor), e.Bounds.X + iconbox.Width + 1, e.Bounds.Y)
        If e.State = DrawItemState.Focus Then
            e.DrawFocusRectangle()
        End If
    End Sub
End Class