Microsoft Internet Information Services (IIS) web servers
Microsoft Internet Information Services (IIS) is a popular type of web server software (the main alternative being Apache). The current version is version 7.0
IIS status code extensions
IIS is distinctive in how it extends the 3-digit HTTP status codes by appending a decimal point and a decimal number that provides a more specific substatus. e.g. a 404.8 error means that the file was not found because a directory that is supposed to hold the file has been hidden. For more examples of these substatus codes, see the pages about these HTTP errors: 400 401 403 404 500 502 503 You may have to disable Internet Explorer friendly HTTP error messages in order to see these extended status codes.
Extra information
- The Official Microsoft IIS Site
- Microsoft WebTopics blog blog about IIS developments
Microsoft Knowledge Base article 943891: “The HTTP status codes in IIS 7.0”