Temporary file during image create trouble

Hello! Can anybody help me with some problem? Here it is. I need to create PNG image with PHP script. When I try to create the image with ImagePNG(), I get warning: "PHP Warning: imagepng: unable to open temporary file in ../../include/Gr_sektor.php on line 413". Image is not created, as you are right thinking. What temporary file? Where is it usually created? How can I change the place to another? Or, may be, I should give some rights for my anonymous user for specific folder (what?). The exterior: Win2000Srv, IIS 5.0, anonimous (IUSR_SERVER2) user for access. Help, please! -- Alexander Rybin ungluker@openpower.ru ICQ: 13391736 Тел./Факс: +7-(08439)-62194 Pager: 8964@mtc.obninsk.ru