Jan 8, 2025 · The Hypertext Transfer Protocol Stack (Http.sys) file blocks IIS from processing the request because of a problem in the request. Typically, this HTTP status code means that the request contains invalid characters or sequences, or that the request goes against the security settings in the Http.sys file.

Aug 23, 2022 · This article talks about HTTP errors as specified in the HTTP RFC (RFC 2616 - section 6.1.1). An HTTP error is always expressed by sending a response with a status code greater than 400 back to the requesting client.

Jan 8, 2025 · Describes the troubleshooting steps to identify the cause of various HTTP 400 errors when using IIS.

Jul 27, 2023 · By default, each logged request in your IIS log will include several key fields including the URL, querystring, and error codes via the status, substatus and win32 status. …

Sep 25, 2020 · Make sure the website has been started in IIS: In the left pane of IIS Manager under "Sites", select the appropriate site. If your site is configured under the "Default Web …

Apr 8, 2025 · IIS defines a number of different 401 errors that indicate a more specific cause of the error. These specific error codes are displayed in the browser but are not displayed in the IIS log: 401.1 - Logon failed. 401.2 - Logon failed due to server configuration. 401.3 - Unauthorized due to ACL on resource. 401.4 - Authorization failed by filter.

Oct 15, 2024 · Learn how to resolve 500 server errors in IIS by leveraging customErrors and httpErrors settings. This comprehensive guide covers error diagnostics, failed...

There are a lot of IIS errors out there. Way too many, right? bad request errors, and application host errors. All these IIS errors sometimes drive you crazy. Here's a list of the most common errors around IIS errors and the proven solution to them: “HTTP Error …

Aug 26, 2024 · If you’re encountering a 503 – Service Unavailable error and notice the Application Pool is stopped, the first step is to check the System event logs. But why does IIS stop the application pool, and why is this configuration included …

Feb 9, 2025 · Troubleshooting IIS is like entering a maze, a 500 Internal Server Error ruining your user’s day, or a 404 Not Found stopping visitors in their tracks. These errors not only affect performance but can also damage your reputation, create angry users, and ultimately affect your revenue if not addressed.