Instructions
Log in to the Xbox Live profile that you encountered the player for which you want to file a complaint.
Press the Xbox 360 logo button in the center of your controller. The "Guide" appears on the screen.
Select "Friends."
Open the "Players" tab.
Select the player for which you want to file a complaint. His profile opens.
Choose "File Complaint."
Choose one of the four categories corresponding with your grievance: "Profile," "Text and Voice Communications," "Video Communications" and "Tampering." A list of complaints appears.
Select a complaint from the list.
Choose "File Complaint."