TUNE0040 Invalid checksum in authorization zap.
This message indicates that the SirTune authorization zap was incorrectly entered. If the zap was manually entered, double check the contents from the original copy. If the zap was received electronically from Sirius Software, either it was modified during receipt or it was incorrectly transmitted. You should double check your steps for receiving it, or obtain a new zap from Sirius Software.