In order to preserve previous selections, you have to hold CTRL key when using mouse. It's standard Windows behavior for multiselect list.

>I have a form with a listbox. When the listbox has focus and I use the arrow keys to navigate up and/or down through the list, the item from which the focus departs becomes highlighted, exactly as if I had selected the item.
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>As long as I continue traversing the list with the up and/or down keys, this behavior continues until all items are highlighted.
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>If I click on the listbox, the highlighted items become unhighlighted except for the item I have clicked on.
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>The listbox has MultiSelect = .T. If I disable MultiSelect, the behavior returns to normal. But since this needs to be a MultiSelect listbox this is not a solution.
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>Any suggestions?
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>Thanks.