virtuemart problem

hi, need help..
when i made a new product without upload the immage it works good.. but when if ada an immage for a category or prduct everithing desappears and it go on this white page with the followig url
http://www.pirotecnicaitalia.it/administrator/index.php

can somebody help me?

Boh!..
i see gavick don't give help like before, it's becoming difficult to use this service