Let's not confuse voice encryption with feature encryption. That's why I asked you to call me. Voice encryption is ILLEGAL to monitor unless you have authorization (i.e., you're an approved system user). What you want is the FEATURE ENCRYPTION file (.ENC) to restore the FEATURE ENCRYPTION on your LPE that I have.
The features in you radio are keyed to the radios ROM serial number. That's the encryption part. M/A-Com applies some sort of algorithm to the mix that gives you a hexadecimal string of 16 characters. Somehow, yours got deleted. I've been trying to contact you by phone to get a better picture of what happened to the radio. The file should be stored on your computer under;
C:\Program Files\MA-COM Software Tools\ProGrammer\backup
and will be your radios ROM S/N .ENC The file directory may be a bit different, depending on which version of ProGrammer you're using.
This posting will give you a good working understanding of what Feature Encryption is, and what it does.
http://www.radioreference.com/forums/showthread.php?t=2325&highlight=feature+encryption