that error comes from not running a 64 bit operating system
the game will not run on a 32 bit OS a 64 bit operating system is a minimum system requirement
if you installed windows 10 64 bit as an upgrade you may also run into file system permission problems
contact ubisoft support
open a support ticket with Ubisoft Support at https://support.ubi.com by clicking on My Questions in the upper left corner of that page.
if they do not answer your ticket ...after a few days (support tickets can take up to 48 hrs to get a response)
try to contact them via social media to see if they can update your ticket (US only)
Facebook: https://www.facebook.com/UbisoftSupport
Twitter: https://twitter.com/ubisoftsupport
(have your support ticket number handy when you try those options)
for Uplay Account Support you can try to contact them by Phone
you can find phone number and support hours information here:https://support.ubi.com/en-US/faq/9/...0000000ee8ACAQ
and here https://support.ubi.com/en-US/FAQ/60...0000000eiChCAI