Updated Apr. 16, 2018

Students trying to access https://acorn.utoronto.ca with a Chrome browser are intermittently not able to reach the authentication page (‘weblogin’ service implemented using Shibboleth) and instead received a template error message “Message did not meet security requirements”.

Problem Information

  1. The issue is reproducible with Chrome browsers and accessing Acorn site only.
  2. The error message displays:  “Message did not meet security requirements.”
  3. There are currently two workarounds:
    1. Clear the browser cache. Subsequent attempts on the same browser show that exact reproduction of the problem may not occur.
    2. There is an option in the Chrome browser “use a prediction service to make pages load quicker” enabled by default. Disabling this setting seems to resolve the problem.


The Acorn service was updated to include HTTP no-cache headers to control the behavior of the Chrome browser.