If you installed this month first Win10 version 1903 cumulative update, KB 4517389, you may be in for a couple of surprises.Mark Busby on AskWoody reported a strange bug shortly after the patch was released:After installing KB4517389 on these Windows systems, when opening 16-bit applications an error message is displayed &unexpected error; quitting.& … After removing the update the application works fine once more.