Designer issue in VS: Events cannot be set on the object passed to the event binding service

I have a little problem: the Winform control (that contains between others WPF) suddenly stopped to be displayed in Designer.

Message:

Events cannot be set on the object passed to the event binding service because a site associated with the object could not be located.

Call Stack:

at System.ComponentModel.Design.EventBindingService.EventPropertyDescriptor.SetValue(Object component, Object value) at System.ComponentModel.Design.Serialization.CodeDomSerializerBase.DeserializeAttachEventStatement(IDesignerSerializationManager manager, CodeAttachEventStatement statement) at System.ComponentModel.Design.Serialization.CodeDomSerializerBase.DeserializeStatement(IDesignerSerializationManager manager, CodeStatement statement)

Where could be the problem?

InitializeComponent code

Private Sub InitializeComponent()
    Dim resources As System.ComponentModel.ComponentResourceManager = New System.ComponentModel.ComponentResourceManager(GetType(PlanDeLigne))
    Dim Appearance1 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance2 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance3 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance4 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance5 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance6 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance7 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance8 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance9 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance10 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance11 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Dim Appearance12 As Infragistics.Win.Appearance = New Infragistics.Win.Appearance()
    Me.mnbMenu = New System.Windows.Forms.ToolStrip()
    Me.mncMode = New System.Windows.Forms.ToolStripComboBox()
    Me.mnbSeparator1 = New System.Windows.Forms.ToolStripSeparator()
    Me.mnbAdd = New System.Windows.Forms.ToolStripButton()
    Me.mnbDelete = New System.Windows.Forms.ToolStripButton()
    Me.mnbSeparator2 = New System.Windows.Forms.ToolStripSeparator()
    Me.mnbDropDownAction = New System.Windows.Forms.ToolStripDropDownButton()
    Me.mnbDropDownActionSens = New System.Windows.Forms.ToolStripMenuItem()
    Me.mnbDropDownActionSeparator1 = New System.Windows.Forms.ToolStripSeparator()
    Me.mnbDropDownActionDistances = New System.Windows.Forms.ToolStripMenuItem()
    Me.mnbDropDownActionSeparator2 = New System.Windows.Forms.ToolStripSeparator()
    Me.mnbDropDownActionArretsPhysiques = New System.Windows.Forms.ToolStripMenuItem()
    Me.mnbSeparator3 = New System.Windows.Forms.ToolStripSeparator()
    Me.mnbSelectionZoom = New System.Windows.Forms.ToolStripButton()
    Me.mnbCancelZoom = New System.Windows.Forms.ToolStripButton()
    Me.mnbSeparator4 = New System.Windows.Forms.ToolStripSeparator()
    Me.mnbParametrage = New System.Windows.Forms.ToolStripButton()
    Me.mncSPlacerArret = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncSSeparator1 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncSImage = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncSDefinirLastArret = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncSSeparator2 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncSSupprimerArrets = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncSInsererArret = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncSSeparator3 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncSInformations = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncSSupprimerSegment = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncSSeparator4 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncSBatirTroncon = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncTInformations = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncTDistances = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncTSeparator1 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncTTempsDeParcours = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncTSeparator2 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncTCreerSensInverse = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncTSeparator3 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncTSupprimerTroncon = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncTBatirItineraire = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncIInformations = New System.Windows.Forms.ToolStripMenuItem()
    Me.mncISeparator1 = New System.Windows.Forms.ToolStripSeparator()
    Me.mncISupprimerItineraire = New System.Windows.Forms.ToolStripMenuItem()
    Me.SplitContainer = New System.Windows.Forms.SplitContainer()
    Me.ElementHost1 = New System.Windows.Forms.Integration.ElementHost()
    Me._StopsCanvas = New Keolis.ctlWpfPlanDeLigne.StopsCanvas()
    Me.lblTitreCreation = New MyNamespace.ctlComponents.Label()
    Me.Panel1 = New System.Windows.Forms.Panel()
    Me.btnOk = New MyNamespace.ctlComponents.Button()
    Me.btnAnnuler = New MyNamespace.ctlComponents.Button()
    Me.grdCreation = New MyNamespace.ctlWinGrid.WinGrid()
    Me.mnbMenu.SuspendLayout()
    CType(Me.SplitContainer, System.ComponentModel.ISupportInitialize).BeginInit()
    Me.SplitContainer.Panel1.SuspendLayout()
    Me.SplitContainer.Panel2.SuspendLayout()
    Me.SplitContainer.SuspendLayout()
    Me.Panel1.SuspendLayout()
    CType(Me.grdCreation, System.ComponentModel.ISupportInitialize).BeginInit()
    Me.SuspendLayout()
    '
    'mnbMenu
    '
    Me.mnbMenu.GripStyle = System.Windows.Forms.ToolStripGripStyle.Hidden
    Me.mnbMenu.Items.AddRange(New System.Windows.Forms.ToolStripItem() {Me.mncMode, Me.mnbSeparator1, Me.mnbAdd, Me.mnbDelete, Me.mnbSeparator2, Me.mnbDropDownAction, Me.mnbSeparator3, Me.mnbSelectionZoom, Me.mnbCancelZoom, Me.mnbSeparator4, Me.mnbParametrage})
    Me.mnbMenu.Location = New System.Drawing.Point(0, 0)
    Me.mnbMenu.Name = "mnbMenu"
    Me.mnbMenu.Size = New System.Drawing.Size(605, 25)
    Me.mnbMenu.TabIndex = 2
    '
    'mncMode
    '
    Me.mncMode.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList
    Me.mncMode.Name = "mncMode"
    Me.mncMode.Size = New System.Drawing.Size(121, 25)
    Me.mncMode.ToolTipText = "Mode du plan de ligne"
    '
    'mnbSeparator1
    '
    Me.mnbSeparator1.AutoSize = False
    Me.mnbSeparator1.Name = "mnbSeparator1"
    Me.mnbSeparator1.Size = New System.Drawing.Size(20, 25)
    '
    'mnbAdd
    '
    Me.mnbAdd.DisplayStyle = System.Wind开发者_StackOverflowows.Forms.ToolStripItemDisplayStyle.Image
    Me.mnbAdd.Image = CType(resources.GetObject("mnbAdd.Image"), System.Drawing.Image)
    Me.mnbAdd.ImageTransparentColor = System.Drawing.Color.Magenta
    Me.mnbAdd.Name = "mnbAdd"
    Me.mnbAdd.Size = New System.Drawing.Size(23, 22)
    Me.mnbAdd.Text = "Création Tronçon / Itinéraire"
    '
    'mnbDelete
    '
    Me.mnbDelete.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image
    Me.mnbDelete.Image = CType(resources.GetObject("mnbDelete.Image"), System.Drawing.Image)
    Me.mnbDelete.ImageTransparentColor = System.Drawing.Color.Magenta
    Me.mnbDelete.Name = "mnbDelete"
    Me.mnbDelete.Size = New System.Drawing.Size(23, 22)
    Me.mnbDelete.Text = "Supprimer les éléments sélectionnés"
    '
    'mnbSeparator2
    '
    Me.mnbSeparator2.AutoSize = False
    Me.mnbSeparator2.Name = "mnbSeparator2"
    Me.mnbSeparator2.Size = New System.Drawing.Size(20, 25)
    '
    'mnbDropDownAction
    '
    Me.mnbDropDownAction.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image
    Me.mnbDropDownAction.DropDownItems.AddRange(New System.Windows.Forms.ToolStripItem() {Me.mnbDropDownActionSens, Me.mnbDropDownActionSeparator1, Me.mnbDropDownActionDistances, Me.mnbDropDownActionSeparator2, Me.mnbDropDownActionArretsPhysiques})
    Me.mnbDropDownAction.Image = CType(resources.GetObject("mnbDropDownAction.Image"), System.Drawing.Image)
    Me.mnbDropDownAction.ImageTransparentColor = System.Drawing.Color.Magenta
    Me.mnbDropDownAction.Name = "mnbDropDownAction"
    Me.mnbDropDownAction.Size = New System.Drawing.Size(29, 22)
    Me.mnbDropDownAction.Text = "Action sur le plan de ligne"
    '
    'mnbDropDownActionSens
    '
    Me.mnbDropDownActionSens.Checked = True
    Me.mnbDropDownActionSens.CheckOnClick = True
    Me.mnbDropDownActionSens.CheckState = System.Windows.Forms.CheckState.Checked
    Me.mnbDropDownActionSens.Name = "mnbDropDownActionSens"
    Me.mnbDropDownActionSens.Size = New System.Drawing.Size(222, 22)
    Me.mnbDropDownActionSens.Text = "Afficher le sens"
    '
    'mnbDropDownActionSeparator1
    '
    Me.mnbDropDownActionSeparator1.Name = "mnbDropDownActionSeparator1"
    Me.mnbDropDownActionSeparator1.Size = New System.Drawing.Size(219, 6)
    '
    'mnbDropDownActionDistances
    '
    Me.mnbDropDownActionDistances.Checked = True
    Me.mnbDropDownActionDistances.CheckOnClick = True
    Me.mnbDropDownActionDistances.CheckState = System.Windows.Forms.CheckState.Checked
    Me.mnbDropDownActionDistances.Name = "mnbDropDownActionDistances"
    Me.mnbDropDownActionDistances.Size = New System.Drawing.Size(222, 22)
    Me.mnbDropDownActionDistances.Text = "Afficher les distances"
    '
    'mnbDropDownActionSeparator2
    '
    Me.mnbDropDownActionSeparator2.Name = "mnbDropDownActionSeparator2"
    Me.mnbDropDownActionSeparator2.Size = New System.Drawing.Size(219, 6)
    '
    'mnbDropDownActionArretsPhysiques
    '
    Me.mnbDropDownActionArretsPhysiques.Checked = True
    Me.mnbDropDownActionArretsPhysiques.CheckOnClick = True
    Me.mnbDropDownActionArretsPhysiques.CheckState = System.Windows.Forms.CheckState.Checked
    Me.mnbDropDownActionArretsPhysiques.Name = "mnbDropDownActionArretsPhysiques"
    Me.mnbDropDownActionArretsPhysiques.Size = New System.Drawing.Size(222, 22)
    Me.mnbDropDownActionArretsPhysiques.Text = "Afficher les arrêts physiques"
    '
    'mnbSeparator3
    '
    Me.mnbSeparator3.AutoSize = False
    Me.mnbSeparator3.Name = "mnbSeparator3"
    Me.mnbSeparator3.Size = New System.Drawing.Size(20, 25)
    '
    'mnbSelectionZoom
    '
    Me.mnbSelectionZoom.CheckOnClick = True
    Me.mnbSelectionZoom.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image
    Me.mnbSelectionZoom.Image = CType(resources.GetObject("mnbSelectionZoom.Image"), System.Drawing.Image)
    Me.mnbSelectionZoom.ImageTransparentColor = System.Drawing.Color.Magenta
    Me.mnbSelectionZoom.Name = "mnbSelectionZoom"
    Me.mnbSelectionZoom.Size = New System.Drawing.Size(23, 22)
    Me.mnbSelectionZoom.Text = "Zoom par sélection"
    '
    'mnbCancelZoom
    '
    Me.mnbCancelZoom.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image
    Me.mnbCancelZoom.Image = CType(resources.GetObject("mnbCancelZoom.Image"), System.Drawing.Image)
    Me.mnbCancelZoom.ImageTransparentColor = System.Drawing.Color.Magenta
    Me.mnbCancelZoom.Name = "mnbCancelZoom"
    Me.mnbCancelZoom.Size = New System.Drawing.Size(23, 22)
    Me.mnbCancelZoom.Text = "Annuler le zoom"
    '
    'mnbSeparator4
    '
    Me.mnbSeparator4.AutoSize = False
    Me.mnbSeparator4.Name = "mnbSeparator4"
    Me.mnbSeparator4.Size = New System.Drawing.Size(20, 25)
    '
    'mnbParametrage
    '
    Me.mnbParametrage.DisplayStyle = System.Windows.Forms.ToolStripItemDisplayStyle.Image
    Me.mnbParametrage.Image = CType(resources.GetObject("mnbParametrage.Image"), System.Drawing.Image)
    Me.mnbParametrage.ImageTransparentColor = System.Drawing.Color.Magenta
    Me.mnbParametrage.Name = "mnbParametrage"
    Me.mnbParametrage.Size = New System.Drawing.Size(23, 22)
    Me.mnbParametrage.Text = "Paramétrage"
    '
    'mncSPlacerArret
    '
    Me.mncSPlacerArret.Name = "mncSPlacerArret"
    Me.mncSPlacerArret.Size = New System.Drawing.Size(216, 22)
    Me.mncSPlacerArret.Text = "Placer un arrêt"
    '
    'mncSSeparator1
    '
    Me.mncSSeparator1.Name = "mncSSeparator1"
    Me.mncSSeparator1.Size = New System.Drawing.Size(213, 6)
    '
    'mncSImage
    '
    Me.mncSImage.Name = "mncSImage"
    Me.mncSImage.Size = New System.Drawing.Size(216, 22)
    Me.mncSImage.Text = "Image..."
    '
    'mncSDefinirLastArret
    '
    Me.mncSDefinirLastArret.Name = "mncSDefinirLastArret"
    Me.mncSDefinirLastArret.Size = New System.Drawing.Size(216, 22)
    Me.mncSDefinirLastArret.Text = "Définir comme dernier arrêt"
    '
    'mncSSeparator2
    '
    Me.mncSSeparator2.Name = "mncSSeparator2"
    Me.mncSSeparator2.Size = New System.Drawing.Size(213, 6)
    '
    'mncSSupprimerArrets
    '
    Me.mncSSupprimerArrets.Name = "mncSSupprimerArrets"
    Me.mncSSupprimerArrets.Size = New System.Drawing.Size(216, 22)
    Me.mncSSupprimerArrets.Text = "Supprimer le ou les arrêts"
    '
    'mncSInsererArret
    '
    Me.mncSInsererArret.Name = "mncSInsererArret"
    Me.mncSInsererArret.Size = New System.Drawing.Size(216, 22)
    Me.mncSInsererArret.Text = "Insérer un arrêt"
    '
    'mncSSeparator3
    '
    Me.mncSSeparator3.Name = "mncSSeparator3"
    Me.mncSSeparator3.Size = New System.Drawing.Size(213, 6)
    '
    'mncSInformations
    '
    Me.mncSInformations.Name = "mncSInformations"
    Me.mncSInformations.Size = New System.Drawing.Size(216, 22)
    Me.mncSInformations.Text = "Modifier les informations"
    '
    'mncSSupprimerSegment
    '
    Me.mncSSupprimerSegment.Name = "mncSSupprimerSegment"
    Me.mncSSupprimerSegment.Size = New System.Drawing.Size(216, 22)
    Me.mncSSupprimerSegment.Text = "Supprimer le segment"
    '
    'mncSSeparator4
    '
    Me.mncSSeparator4.Name = "mncSSeparator4"
    Me.mncSSeparator4.Size = New System.Drawing.Size(213, 6)
    '
    'mncSBatirTroncon
    '
    Me.mncSBatirTroncon.Name = "mncSBatirTroncon"
    Me.mncSBatirTroncon.Size = New System.Drawing.Size(216, 22)
    Me.mncSBatirTroncon.Text = "Bâtir un tronçon"
    '
    'mncTInformations
    '
    Me.mncTInformations.Name = "mncTInformations"
    Me.mncTInformations.Size = New System.Drawing.Size(201, 22)
    Me.mncTInformations.Text = "Modifier les informations"
    '
    'mncTDistances
    '
    Me.mncTDistances.Name = "mncTDistances"
    Me.mncTDistances.Size = New System.Drawing.Size(201, 22)
    Me.mncTDistances.Text = "Modifier les distances"
    '
    'mncTSeparator1
    '
    Me.mncTSeparator1.Name = "mncTSeparator1"
    Me.mncTSeparator1.Size = New System.Drawing.Size(198, 6)
    '
    'mncTTempsDeParcours
    '
    Me.mncTTempsDeParcours.Name = "mncTTempsDeParcours"
    Me.mncTTempsDeParcours.Size = New System.Drawing.Size(201, 22)
    Me.mncTTempsDeParcours.Text = "Temps de parcours"
    '
    'mncTSeparator2
    '
    Me.mncTSeparator2.Name = "mncTSeparator2"
    Me.mncTSeparator2.Size = New System.Drawing.Size(198, 6)
    '
    'mncTCreerSensInverse
    '
    Me.mncTCreerSensInverse.Name = "mncTCreerSensInverse"
    Me.mncTCreerSensInverse.Size = New System.Drawing.Size(201, 22)
    Me.mncTCreerSensInverse.Text = "Créer le sens inverse"
    '
    'mncTSeparator3
    '
    Me.mncTSeparator3.Name = "mncTSeparator3"
    Me.mncTSeparator3.Size = New System.Drawing.Size(198, 6)
    '
    'mncTSupprimerTroncon
    '
    Me.mncTSupprimerTroncon.Name = "mncTSupprimerTroncon"
    Me.mncTSupprimerTroncon.Size = New System.Drawing.Size(201, 22)
    Me.mncTSupprimerTroncon.Text = "Supprimer le tronçon"
    '
    'mncTBatirItineraire
    '
    Me.mncTBatirItineraire.Name = "mncTBatirItineraire"
    Me.mncTBatirItineraire.Size = New System.Drawing.Size(201, 22)
    Me.mncTBatirItineraire.Text = "Bâtir un itinéraire"
    '
    'mncIInformations
    '
    Me.mncIInformations.Name = "mncIInformations"
    Me.mncIInformations.Size = New System.Drawing.Size(201, 22)
    Me.mncIInformations.Text = "Modifier les informations"
    '
    'mncISeparator1
    '
    Me.mncISeparator1.Name = "mncISeparator1"
    Me.mncISeparator1.Size = New System.Drawing.Size(198, 6)
    '
    'mncISupprimerItineraire
    '
    Me.mncISupprimerItineraire.Name = "mncISupprimerItineraire"
    Me.mncISupprimerItineraire.Size = New System.Drawing.Size(201, 22)
    Me.mncISupprimerItineraire.Text = "Supprimer l'itinéraires"
    '
    'SplitContainer
    '
    Me.SplitContainer.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D
    Me.SplitContainer.Dock = System.Windows.Forms.DockStyle.Fill
    Me.SplitContainer.FixedPanel = System.Windows.Forms.FixedPanel.Panel2
    Me.SplitContainer.Location = New System.Drawing.Point(0, 25)
    Me.SplitContainer.Name = "SplitContainer"
    '
    'SplitContainer.Panel1
    '
    Me.SplitContainer.Panel1.AutoScroll = True
    Me.SplitContainer.Panel1.Controls.Add(Me.ElementHost1)
    '
    'SplitContainer.Panel2
    '
    Me.SplitContainer.Panel2.Controls.Add(Me.lblTitreCreation)
    Me.SplitContainer.Panel2.Controls.Add(Me.Panel1)
    Me.SplitContainer.Panel2.Controls.Add(Me.grdCreation)
    Me.SplitContainer.Panel2MinSize = 0
    Me.SplitContainer.Size = New System.Drawing.Size(605, 418)
    Me.SplitContainer.SplitterDistance = 428
    Me.SplitContainer.SplitterWidth = 2
    Me.SplitContainer.TabIndex = 1
    '
    'ElementHost1
    '
    Me.ElementHost1.Dock = System.Windows.Forms.DockStyle.Fill
    Me.ElementHost1.Location = New System.Drawing.Point(0, 0)
    Me.ElementHost1.Name = "ElementHost1"
    Me.ElementHost1.Size = New System.Drawing.Size(424, 414)
    Me.ElementHost1.TabIndex = 0
    Me.ElementHost1.Text = "ElementHost1"
    Me.ElementHost1.Child = Me._StopsCanvas
    '
    'lblTitreCreation
    '
    Me.lblTitreCreation.Anchor = CType(((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Left) _
                Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
    Me.lblTitreCreation.Location = New System.Drawing.Point(3, 4)
    Me.lblTitreCreation.Name = "lblTitreCreation"
    Me.lblTitreCreation.Size = New System.Drawing.Size(167, 16)
    Me.lblTitreCreation.TabIndex = 4
    '
    'Panel1
    '
    Me.Panel1.AutoSize = True
    Me.Panel1.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink
    Me.Panel1.Controls.Add(Me.btnOk)
    Me.Panel1.Controls.Add(Me.btnAnnuler)
    Me.Panel1.Dock = System.Windows.Forms.DockStyle.Bottom
    Me.Panel1.Location = New System.Drawing.Point(0, 385)
    Me.Panel1.Name = "Panel1"
    Me.Panel1.Size = New System.Drawing.Size(171, 29)
    Me.Panel1.TabIndex = 3
    '
    'btnOk
    '
    Me.btnOk.Anchor = CType((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
    Me.btnOk.BackColor = System.Drawing.SystemColors.Control
    Me.btnOk.FlatAppearance.MouseDownBackColor = System.Drawing.Color.LightSlateGray
    Me.btnOk.FlatAppearance.MouseOverBackColor = System.Drawing.Color.LightSteelBlue
    Me.btnOk.FlatStyle = System.Windows.Forms.FlatStyle.Flat
    Me.btnOk.Font = New System.Drawing.Font("Microsoft Sans Serif", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
    Me.btnOk.ForeColor = System.Drawing.SystemColors.ControlText
    Me.btnOk.Location = New System.Drawing.Point(12, 3)
    Me.btnOk.Name = "btnOk"
    Me.btnOk.Size = New System.Drawing.Size(75, 23)
    Me.btnOk.TabIndex = 6
    Me.btnOk.Text = "OK"
    Me.btnOk.UseVisualStyleBackColor = True
    '
    'btnAnnuler
    '
    Me.btnAnnuler.Anchor = CType((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
    Me.btnAnnuler.BackColor = System.Drawing.SystemColors.Control
    Me.btnAnnuler.DialogResult = System.Windows.Forms.DialogResult.Cancel
    Me.btnAnnuler.FlatAppearance.MouseDownBackColor = System.Drawing.Color.LightSlateGray
    Me.btnAnnuler.FlatAppearance.MouseOverBackColor = System.Drawing.Color.LightSteelBlue
    Me.btnAnnuler.FlatStyle = System.Windows.Forms.FlatStyle.Flat
    Me.btnAnnuler.Font = New System.Drawing.Font("Microsoft Sans Serif", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
    Me.btnAnnuler.ForeColor = System.Drawing.SystemColors.ControlText
    Me.btnAnnuler.Location = New System.Drawing.Point(93, 3)
    Me.btnAnnuler.Name = "btnAnnuler"
    Me.btnAnnuler.Size = New System.Drawing.Size(75, 23)
    Me.btnAnnuler.TabIndex = 7
    Me.btnAnnuler.Text = "Annuler"
    Me.btnAnnuler.UseVisualStyleBackColor = True
    '
    'grdCreation
    '
    Me.grdCreation.Anchor = CType((((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Bottom) _
                Or System.Windows.Forms.AnchorStyles.Left) _
                Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
    Me.grdCreation.AutoResizeColumns = False
    Me.grdCreation.ColumnsFiltreActif = False
    Appearance1.BackColor = System.Drawing.SystemColors.Window
    Appearance1.BorderColor = System.Drawing.SystemColors.InactiveCaption
    Me.grdCreation.DisplayLayout.Appearance = Appearance1
    Me.grdCreation.DisplayLayout.BorderStyle = Infragistics.Win.UIElementBorderStyle.Solid
    Me.grdCreation.DisplayLayout.CaptionVisible = Infragistics.Win.DefaultableBoolean.[False]
    Appearance2.BackColor = System.Drawing.SystemColors.ActiveBorder
    Appearance2.BackColor2 = System.Drawing.SystemColors.ControlDark
    Appearance2.BackGradientStyle = Infragistics.Win.GradientStyle.Vertical
    Appearance2.BorderColor = System.Drawing.SystemColors.Window
    Me.grdCreation.DisplayLayout.GroupByBox.Appearance = Appearance2
    Appearance3.ForeColor = System.Drawing.SystemColors.GrayText
    Me.grdCreation.DisplayLayout.GroupByBox.BandLabelAppearance = Appearance3
    Me.grdCreation.DisplayLayout.GroupByBox.BorderStyle = Infragistics.Win.UIElementBorderStyle.Solid
    Appearance4.BackColor = System.Drawing.SystemColors.ControlLightLight
    Appearance4.BackColor2 = System.Drawing.SystemColors.Control
    Appearance4.BackGradientStyle = Infragistics.Win.GradientStyle.Horizontal
    Appearance4.ForeColor = System.Drawing.SystemColors.GrayText
    Me.grdCreation.DisplayLayout.GroupByBox.PromptAppearance = Appearance4
    Me.grdCreation.DisplayLayout.MaxColScrollRegions = 1
    Me.grdCreation.DisplayLayout.MaxRowScrollRegions = 1
    Appearance5.BackColor = System.Drawing.SystemColors.Window
    Appearance5.ForeColor = System.Drawing.SystemColors.ControlText
    Me.grdCreation.DisplayLayout.Override.ActiveCellAppearance = Appearance5
    Appearance6.BackColor = System.Drawing.SystemColors.Highlight
    Appearance6.ForeColor = System.Drawing.SystemColors.HighlightText
    Me.grdCreation.DisplayLayout.Override.ActiveRowAppearance = Appearance6
    Me.grdCreation.DisplayLayout.Override.AllowRowFiltering = Infragistics.Win.DefaultableBoolean.[False]
    Me.grdCreation.DisplayLayout.Override.BorderStyleCell = Infragistics.Win.UIElementBorderStyle.Dotted
    Me.grdCreation.DisplayLayout.Override.BorderStyleRow = Infragistics.Win.UIElementBorderStyle.Dotted
    Appearance7.BackColor = System.Drawing.SystemColors.Window
    Me.grdCreation.DisplayLayout.Override.CardAreaAppearance = Appearance7
    Appearance8.BorderColor = System.Drawing.Color.Silver
    Appearance8.TextTrimming = Infragistics.Win.TextTrimming.EllipsisCharacter
    Me.grdCreation.DisplayLayout.Override.CellAppearance = Appearance8
    Me.grdCreation.DisplayLayout.Override.CellPadding = 0
    Appearance9.BackColor = System.Drawing.SystemColors.Control
    Appearance9.BackColor2 = System.Drawing.SystemColors.ControlDark
    Appearance9.BackGradientAlignment = Infragistics.Win.GradientAlignment.Element
    Appearance9.BackGradientStyle = Infragistics.Win.GradientStyle.Horizontal
    Appearance9.BorderColor = System.Drawing.SystemColors.Window
    Me.grdCreation.DisplayLayout.Override.GroupByRowAppearance = Appearance9
    Appearance10.TextHAlignAsString = "Left"
    Me.grdCreation.DisplayLayout.Override.HeaderAppearance = Appearance10
    Me.grdCreation.DisplayLayout.Override.HeaderClickAction = Infragistics.Win.UltraWinGrid.HeaderClickAction.SortMulti
    Me.grdCreation.DisplayLayout.Override.HeaderStyle = Infragistics.Win.HeaderStyle.WindowsXPCommand
    Appearance11.BackColor = System.Drawing.SystemColors.Window
    Appearance11.BorderColor = System.Drawing.Color.Silver
    Me.grdCreation.DisplayLayout.Override.RowAppearance = Appearance11
    Me.grdCreation.DisplayLayout.Override.RowSelectors = Infragistics.Win.DefaultableBoolean.[False]
    Appearance12.BackColor = System.Drawing.SystemColors.ControlLight
    Me.grdCreation.DisplayLayout.Override.TemplateAddRowAppearance = Appearance12
    Me.grdCreation.DisplayLayout.ScrollBounds = Infragistics.Win.UltraWinGrid.ScrollBounds.ScrollToFill
    Me.grdCreation.DisplayLayout.ScrollStyle = Infragistics.Win.UltraWinGrid.ScrollStyle.Immediate
    Me.grdCreation.DisplayLayout.ViewStyleBand = Infragistics.Win.UltraWinGrid.ViewStyleBand.OutlookGroupBy
    Me.grdCreation.Font = New System.Drawing.Font("Times New Roman", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
    Me.grdCreation.Location = New System.Drawing.Point(0, 23)
    Me.grdCreation.Name = "grdCreation"
    Me.grdCreation.PrintColumnsKey = Nothing
    Me.grdCreation.PrintRowsIndex = Nothing
    Me.grdCreation.PrintTitle = Nothing
    Me.grdCreation.RowsActivation = Infragistics.Win.UltraWinGrid.Activation.AllowEdit
    Me.grdCreation.Size = New System.Drawing.Size(175, 391)
    Me.grdCreation.TabIndex = 5
    Me.grdCreation.Tag = ""
    '
    'PlanDeLigne
    '
    Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
    Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
    Me.Controls.Add(Me.SplitContainer)
    Me.Controls.Add(Me.mnbMenu)
    Me.MinimumSize = New System.Drawing.Size(605, 431)
    Me.Name = "PlanDeLigne"
    Me.Size = New System.Drawing.Size(605, 443)
    Me.mnbMenu.ResumeLayout(False)
    Me.mnbMenu.PerformLayout()
    Me.SplitContainer.Panel1.ResumeLayout(False)
    Me.SplitContainer.Panel2.ResumeLayout(False)
    Me.SplitContainer.Panel2.PerformLayout()
    CType(Me.SplitContainer, System.ComponentModel.ISupportInitialize).EndInit()
    Me.SplitContainer.ResumeLayout(False)
    Me.Panel1.ResumeLayout(False)
    CType(Me.grdCreation, System.ComponentModel.ISupportInitialize).EndInit()
    Me.ResumeLayout(False)
    Me.PerformLayout()
End Sub

Take any delegate or event handler registrations out of InitializeComponent. Although the objects are properly created and it all compiles and works fine it seems to screw up the form designer in VS2005.

I've put in a RegisterHandlers method that I call manually on all custom forms. It's not ideal but it works

Just experienced the same error in VS 2017. The cause was that I used the VB keyword Handles obj.event, where obj was a WPF object, contained in the WinForms form. Replacing Handles with a pair of AddHandler / RemoveHandler solved the issue.