This may sound hilarious but gave me quite a start. My (Windows) server has automatic updates switched on. Once in a while it reboots, never a problem. Until last night. In the drive was still a (bootable) disk. After reboot it’s been prompting all night whether I wanted to install a 32-bit or the 64-bit version instead of firing up my web and mail server again.Lesson learned: check and double check if the drive is empty after finishing maintenance.