"400 Error" messages

I keep getting these error messages when I try to access library resources like articles and my interlibrary loan (ILL) account. What's going on?

This is the result of a buildup of cookies being sent from the browser to the website.

Often, you can resolve this by clearing the cache of the browser you’re currently using. This often does the trick. 

  • If you prefer to test this out first, try accessing the page in another browser, or in the private or incognito window of your preferred browser. 
  • In most laptop browsers, just click on File- New Private Window (For Chrome, it’s “New Incognito Window.”)
    • for more assistance, click on the "clearing the cache" link above for HUIT's guidance. 

Want to know more about why this happens? Here's a more detailed explanation:

When you visit a website, your browser sends all the cookie files related to that website's domain name with your request. This includes cookies from all subdomains of the site. For example, if you visit any site ending in "harvard.edu", the browser will send all cookies associated with "harvard.edu", whether from peoplesoft.hrapps.harvard.edu, wiki.harvard.edu, or other subdomains. This helps different parts of the website work together, like allowing you to stay logged in across different services.

However, when accessing electronic resources through a library proxy, the situation escalates. The proxy changes the URL to route through "harvard.edu", making external sites like JSTOR recognize you as coming from a Harvard IP address. This causes even cookies from these external sites to be stored as "harvard.edu" cookies. Consequently, when you access any Harvard-related link, especially through a proxy, your browser ends up transmitting a massive amount of cookie data.

This builds up until the total size of the request is too large for the browser to handle, and it results in the error message.  Library Technology Services is actively working on a solution, but until then the best option is to clear your browser cache when the buildup occurs.

 

If this information does not seem to apply to your situation, contact us at Ask a Librarian.

If you have reason to believe there could be something going on with your ID, contact the Library Access & Borrowing Office: hl_accessborrowing@harvard.edu or 617-495-4166.

Service Alert:
  • Ask a Librarian, including chat and email, will be suspended Thursday July 4 through Sunday, July 7, 2024, in observance of the holiday weekend. Any questions received during this period will be answered beginning Monday, July 8.
  • If If you're experiencing an ongoing technical issue when you attempt to access library materials with your HarvardKey during these times, please report it to Library Technology Services.

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