php headers already sent error [duplicate]

Question

Possible Duplicate:
Headers already sent by PHP

I have a single php file, with this code in it:

<?php header("Location: somepage.php"); ?>

Absolutely no spaces before or after the php opening or closing tags and I am getting the

Warning: Cannot modify header information - headers already sent by (output started at C:\ ... \test.php:1

Usually when I get this error, the 1 is the line number of the problem, but in this case line one doesn't have any extra whitespace. I only have this code on the page and I am not including any other files.

I'm using xampp on windows xp. Any ideas what's going on or how I can track down what's really causing the problem.

Thanks

Answer 1

Chances are that you have what's known as a BOM (Byte Order Mark) in the file. Depending on what editor you're using, you'll need to turn off adding the BOM...