I purchased my Discover about 9 months ago from Radio Shack. Since then I have managed to lose my receipt. Within the first 60 days I had to do a master factory days reset because I couldn't access the internet. Less than 30 days later I had to do it agai
The device will be repaired by checking the IMEI number of the device even the receipt is lost. But if you want to exchange the accessories, you will have to have the receipt. So generally if the issue is with the device and sending for repair , even if the receipt is not there, that is fine. The device can be repaired for free if it is under warranty.