Original post by: Chris Green ,
Go to xbox.com and sign in with your windows live ID (If you don't have one, make it) and then select the register a console option. You will need to enter your consoles serial number (Under the faceplate above the USB ports) and register your console. You can then go to the "Request a Repair" option, and select the option to have your console repaired (It has a 3 year warrenty for the 3 red rings[3/4 Ring Red] and the e74 error as long as the silver "Microsoft" Sticker under the faceplate hasn't been tampered with or removed.) They will mail you a box, shipping label, packageing, and instructions, then you can package it, and take it to a UPS store where they will ship it for free as long as you attatch the included shipping label. Once microsoft has repaired it, they send it back (The repair process ususually takes 14-21 days) and give you a free 1 Month Xbox live gold card (If you have an Xbox Like Gold Membership) I have repaired my own 360, but since microsoft will do it for free, I would reccomend sending it to them, unless the microsoft warrenty sticker is damaged, or missing.