Wrong username or password.
HOTS is developed to support the functionality of the Google Chrome and Mozilla Firefox browsers. Using other browsers than these two may result in unexpected behavior.
According to W3Schools Famous Month-by-Month Browser Statistics these two browsers are used for more than 90 % of all requests to the W3Schools website (October 2018). It is assumed that a matching browser usage is found for access to HOTS.
You may download Google Chrome or Mozilla Firefox from the links below:
