I have the property "AutoPopDelay" set to 60000, but every time I hover over an associated element, the balloon only stays open for 5 seconds even when my mouse pointer stays over stationary over the element.
Any ideas on what could be causing this?
Edit: I am using WinForms
Reading the documentation for the AutoPopDelay on MSDN (link) the maximum time you can delay a popup is 5000 milliseconds.
If you want a longer duration, use the Show method to control the exact moment when the ToolTip is displayed.
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However, I believe that you are trying to cure the symptoms and not the cause of your problem if you need a ToolTip to stay open for that long. A tool tip is, by definition, is "a small box with contextual information about the item the user to pointing to". If the user is unable to read what the tooltip is trying to suggest in 5 seconds, then it is not really a "tip" but an entire chapter from the help file.
Playing around with the tool tip control a bit it seems you can set AutoPopDelay to anything up to 32767 anything above that and it will default back down to 5000. My guess is in the background a short is being used rather then a int.
来源：https://stackoverflow.com/questions/3906531/tooltip-balloon-disappears-after-5-seconds