Windows Forms ToolTip will not re-appear after first use

Question

I have a Windows Forms C# application where I would like to use a tooltip on one of the text boxes. I initialize the tool-tip in the constructor of the Form class, and it wo

Answer 1

I had a similar problem today. Sometimes, the tooltip would not show. I had one ToolTip control for all the controls in my form.

I also had a MouseEnter event on all the controls added automatically, so I modified the MouseEnter event to do:

_tooltip.Active = false;
_tooltip.Active = true;

It fixed the bug, but I don't know why.

Also, the bug always happened on Windows XP machines, but not on Windows Vista.