I’m unable to update docker on my system which is Windows 10 Pro version 1803 ( Build 17134.706) . I get a message asking to install update but once i choose to update the message disappears and there is no update whatsoever. My current docker version is 17.03.1-ce-rc1-win3 (10625).
In this case I would say the simplest is to go to the download page and install the new version manually. If you’re using a 3rd-party firewall, remember that after an update it may block the shared drives.