404 Not Found

The URL used does not refer to any document. This might have been caused by different things, such as any of the following:

1. You have followed a link on a page, and the page author had mistyped the URL in the link.
2. The document you tried to access does not exist any more. This is not probable.
3. If you had seen a URL in printed media, maybe there was a typo in it.
4. If you typed the URL, maybe some character was mistyped.

If you had typed the URL, please check especially the following possibilities:

• Perhaps the URL contains lower case letters instead of upper case letters that you typed, or vice versa? URLs are case-sensitive, generally speaking. Mostly my URLs are in all lower case.
• A space somewhere? A URL must not contain a blank (space) character.
• Check whether there are some extra characters at the end of the URL, or perhaps some character missing.

You might find what you are looking for by looking at the index page of my documents in English.

Or you might try keyword searches:

If you encountered this problem when following a link on my pages, I'd appreciate a note about it. Please specify the referring page and the name or URL of the link.

Check the language preferences in your browser!

You got this version of the error page because your browser did not report your language preferences to the server, or reported preferences that do not contain English at all. If you understand English at all, you are encouraged to modify your browser's language preferences to include English. At the same time, check the preferences as a whole. For instructions, consult the document Language selection in browsers.

In this particular case, the normal error page in English has the same content as this page, except for this note on language negotiation. But in general, you could benefit a lot from the possibility of getting a version selected by your real language preferences.

Technical explanations

This is a customized error page which is sent as response to requests for URLs that begin with http://jkorpela.fi/ but do not correspond to any existing document, i.e. the server sends HTTP error code 404, normally because the requested resource does not exist. The goal is simply to provide some advice in trying to locate the resource which the user is looking for. I have written some notes on the technique.

Note to Finnish readers: Tästä virheilmoitussivusta on myös suomenkielinen versio. Jos päädyit tähän englanninkieliseen versioon vaikka osaat suomea paremmin kuin englantia, tarkista selaimesi kieliasetukset!