I am confused… You didn’t specify a user for setting the password. I would presume that either one of 2 things should have happened. Either the query would have failed, and thus no changes OR the query would have reset ALL passwords, at which time you would need to use the new password.
That being said, if there is now a new password (including for ROOT) then using
mysql.exe -u root
SHOULD fail as you did not present a password. You would need to do one of the following:
mysql.exe -u root -p newpwd
mysql.exe -u root -p
The later of which would PROMPT you for the password.