I have source tree pinned to my taskbar (by right clicking on the icon and choosing 'pin to taskbar'), but whenever I allow SourceTree to update itself it is lost from the taskbar.

If I try to open it without rebooting then I get a dialog saying "Can't open this item. It might have been moved, renamed, or deleted. Do you want to remove this item? Yes/No". Whatever I click the icon gets removed.

The icon in the start menu continues to work.