ToolTip property doesn't alow you to create multiline ToolTip. You can use a label instead to show the tooltip.


Code:
Private Function TimeOut(pInterval As Single)
    Dim sngTimer As Single
    
    sngTimer = Timer
    Do While Timer < sngTimer + pInterval
        DoEvents
    Loop
End Function


Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
    lblToolTip.Visible = False
End Sub


Private Sub Text1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
    TimeOut 0.3
    lblToolTip.Caption = "This is a" & vbCrLf & "multilline ToolTip demo"
    lblToolTip.Left = Text1.Left + lblToolTip.Width
    lblToolTip.Top = Text1.Top + Text1.Height
    lblToolTip.Visible = True
End Sub