Last modified: 2007-03-01 15:42:52 UTC
Although wikitext such as [[links]] show correctly when you edit the MediaWiki page itself, they don't show correctly in actual usage. You can prompt this error message by going to Special:Upload and changing the destination filename to something without a file extension, or a disallowed extension (like .mp3).
It's also collapsing all whitespace which is not so useful.
Also, a comment from http://commons.wikimedia.org/wiki/MediaWiki_talk:Badfiletype : "It looks like $1 is never an empty string, even when you have no extension, yet the html code of the page will not give the its value." This is a problem because we want to user parser functions to account for two distinct mistakes (no extension/bad extension) which both result in this error warning, but we can't.
Or, simply parserfunctions might not be able to handle the $1 variable.
MediaWiki:Badfiletype splitted in r20100 into 3 new messages: filetype-missing: for files without extension (wikisyntax enanbled) filetype-badtype: for files of unwanted types. The list of enabled types will be shown as $2 (wikisyntax enabled) filetype-badmime: for invalid mime types (no wikisyntax)