On my board one of my users accused me in accepting pornography game banner in ads column on the right right before Christmas that shows my level of low morale and total ignorance of ethical norms. She is problem user and write flaming and drama posts on the regular basis and has warnings from other board mods. She attached printscreen that I am sure is fraud, because no that kind of banner appeared on my website, it against policy and my personal believs. Advertising agency also denied this fact. I am not good at any graphic software and don't understand how could I prove that this printscreen is fraud. Any help? And sorry for my bad English.