>>It's OK, I figured it out. Thanks.
>
>Could you please explain your solution? I was thinking about the problem, but haven't come up with anything in my mind except for setting it in GotFocus and back in LostFocus. Don't know if this is a good idea or not.

Seems to me GotFocus/LostFocus won't help, since tooltips are about mouse hovering. But I think you could use MouseEnter/MouseLeave.

Tamar