In the conference homepage header section, I am able to upload jpgs and gifs but not pngs. The error message is:
Invalid homepage header title image format or upload failed. Accepted formats are .gif, .jpg, or .png.
The phpinfo output is herehttp://semiofest.com/phpinfo.php
Any help appreciated. This is rather urgent as I have to have the web site up and running as soon as possible.