I was having problems validating my new OPML “feed” at Randy Charles Morin’s KBCafe Really Simple Validation engine - I kept getting a 404 error. Same kind of error at Julian Bond’s OPML Browser at Voidstar. Then I discovered that my RSS feeds exhibited the same problem, though they could be subscribed to and viewed in the browser.

Turns out there’s a bug that’s fixed in WP 1.5.1 (I’m a little behind on upgrades) having to do with rewrites and server paths. Essentially WP was checking for “index.php” in the url and when it didn’t find it it went into the rewrite rule engine to find out if there was really a 404 - Not Found error (in the process assuming a Not Found as a given). Neither of the urls I was using had “index.php” in them, the code caught my url and passed a 404 HTTP header, causing both of the above-mentioned services to think that they couldn’t find my file. Simply removing “index” from the code fixed the problem (until I get around to running the update).

The moral of the story? Try googling the error before you spend the evening poking around in the code (yep, that’d be hit #1 that led me to the fix).

And now back to your regularly scheduled program.