I do not know how but I am very much sure that my desktop is infected by a threat. It says something as Zero Day Powerpoint vulnerability whenever I try to open my Microsoft Powerpoint. I am using PowerPoint 2003 Service Pack 3. My operating system is Windows XP. I am not able to terminate this malicious program. This has also infected my laptop that has Mac installed and I am using Microsoft Office 2004 for Mac on my laptop. Please need help.