requiring global.php on a non-vb page results in blank page?

[bigtime]

Hi,

I have a non vb php page. When I put this at the top, I get a blank page. What could be causing that?

require_once('/usr/local/home/domain.com/httpdocs/testvb/global.php');

I tried this too:

chdir('/usr/local/home/domain.com/httpdocs/testvb/');
require_once('./global.php');

Thanks,

Tim