Headers!!

[Elhombrebala]

At the begiining of my page I have this code:

session_start();
if (!isset($_SESSION['user']) && !isset($_SESSION['lang'])){
header("Location: entry.php?baduser=1");
}

After doing some work, I try to redirect people by using:

header("Location: mainpage.php?edit=".$edit);

And then I get the infamous message:

Warning: Cannot modify header information - headers already sent by

What's going on?

[planetsim]

You cannot have any output html/php errors etc before a header is sent you will get that error.

[Weedpacket]

What, for example, does it say on the line where the error message says "Output started at..."?

[Elhombrebala]

The error is output in line 58:

<script src="js_quicktags4.js" type="text/javascript"></script>

[thorpe]

you might want to take a llok into output buffering ([man]ob_start[/man]), i find it the easiest way to get around these errors.

[LoganK]

You're outputting some sort of code before the headers. This is what's causing it to fail. You can't have any thing at all, even whitespace, before you call the header function. If output is require take a look at just echoing a simple JavaScript command:

echo "<script>location='blah.php'</script>";