To fix it for you, try to run the affecting php script through the cgi from the command line and use strace to see which file it is really trying to access, e.g.

strace -e trace=open php-cgi -f script.php

Try to avoid the imagejpeg() call so you don't clutter your terminal with binary data.

Try it without the .ttf extension.

I just had same kind of problem on Linux. And the reason
was that the user my apache runs as did not have read 
access to the fonts. So you might wanna check that too.

@mfischer:

I made a test with file_monitor on WinXP.

TestScript:
<?PHP
$im = imagecreate(420,315);
$grey = imagecolorallocate($im, 60, 60, 60);
imagettftext($im, 80, 0, 20, 50, $grey, 'font.ttf', 'test');
?>

Path of the Testscript: E:\try\test.php4
The php.exe tried to open the fontfile (E:\try\font.ttf) on the following location: 

17:44:45   php.exe   FASTIO_QUERY_OPEN
E:\usr\share\fonts\truetype\E:\try\font.ttf.ttf
FAILURE

I have not so much experience, but everywhere in the GD- or in the FreeType-code must be this fixed path:\usr\share\fonts\truetype\

This bug has been fixed in CVS. You can grab a snapshot of the
CVS version at http://snaps.php.net/. In case this was a documentation 
problem, the fix will show up soon at http://www.php.net/manual/.
In case this was a PHP.net website problem, the change will show
up on the PHP.net site and on the mirror sites.
Thank you for the report, and for helping us make PHP better.

You have to set the GDFONTPATH environment variable before yuo call the ttftext function, e.g.

putenv("GDFONTPATH=...");

but chances may be that it doesn't work with the gd version 4.2.0 is linked against.

However this is fixed in http://snaps.php.net/win32/php4-win32-latest.zip , so closing.

I believe this bug is not fixed.
Script E:\try\test\test.php
Font E:\try\gd\font.ttf

putenv("GDFONTPATH=E:\try\gd\");
imagettftext($im, 20, 0, 10, 5, $grey, 'font.ttf', 'beep');

Apache.exe tried to open E:\try\gd\e:\try\test\font.ttf.ttf

putenv("GDFONTPATH=");
imagettftext($im, 20, 0, 10, 5, $grey, 'font.ttf', 'beep');

Apache.exe tried to open C:\winnt\fonts\e:\try\test\font.ttf.ttf

But my WinXP is in c:\XP. This hardcoded Path (C:\winnt\) is a bad idea.

My provider has php 4.2.3 and I sorrily can't upgrade his php... ;-)
My code is this:

...
$bild = $_GET["bild"];
header("Content-type: image/png");
$img = imagecreatefrompng("../bin/B_Jahr.png");
$hc = imagecolorallocate($img,0,0,0);
$tsize = 11;
$xpos = 7;
$ypos = 15;
imagettftext($img,$tsize,0,$xpos,$ypos,$hc,"../bin/comic.ttf",$bild);
imagepng($img);
imagedestroy($img);
...

and it worked fine until my provider upgraded the version to 4.2.3. It's a huge German provider (1&1) and they are not able to upgrade quickly.

Is there any workaround for the ttf-problem instead?
Absolute path didn't work.

Thankful

Peter