Have you ever taken a closer look at the powerful Computer Management utility that comes with the XP Professional administrative tools? No? Well Microsoft might have included a little surprise for you... You can manage all computer user accounts with this tool and surprise: an undocumented support account is included! Read more... Screenshot: When you log on to Windows not all user accounts are displayed (see guest account - needs to be enabled manually). Unfortunately Microsoft has included another undocumented account SUPPORT_388945a0. According to Microsoft this account is only required for OEM usage. Though normally deactivated in our opinion a security risk might lie within. An undocumented account with no discernible use to the user is at least questionable. It could be only a question of time in which this account becomes activated (via which way is another question). If there would be a default password for this account it would spread Windows doors wide open. One can delete this account by pressing the delete key on the keyboard. You can find it via: Settings -> Control Panel -> Administrative Tools -> Computer Management | Local Users and Groups -> Users