Question Coby Upgrade Help Needed

Hai All i am using a coby tablet and i want to upgrade its version to 4.0

coby offers this by their app check attachment

i dowloaded and installed it but typed the serial number wrong and when i retyped it it says your tablet is already registred with another serial number

can you help me fix it and upgrade my android from 2.3 to 4.0?
Attached Files
File Type: apk UpgradeAndroid.apk - [Click for QR Code] (150.9 KB, 5 views)