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Sohail Pathan
Sohail Pathan

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What is a 400 Bad Request?

The HTTP 400 Bad Request is a generic client error that occurs when a browser sends a request to a web server and the server cannot understand or process this request correctly.



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Possible/Most common causes:

  • Typos in the URL String: When there is a typo in the source URL that leads to an invalid destination.

  • The file size is too large: When the request body or file exceeds the server’s maximum allowed capacity.

  • Corrupted browser Cache & Cookies: When the stored cache or cookies are corrupted.

  • Outdated DNS Cache: When an outdated DNS cache sends a request to the wrong server address.

How to Fix a 400 Bad Request?

  • Make sure the URL is written correctly and matches the server destination.

  • Servers have limitations on the size of data they can handle. Trim down the request if it exceeds any size restrictions.

  • If the DNS information is outdated, flush the DNS cache to update the latest information.

  • Check if the headers are formatted correctly and include all necessary data.

  • Ensure the server is configured to handle requests appropriately, including size limits and header configurations.

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