I just purchased NetLib's Encryptionizer DE

It's great. The encrypted files are decrypted dynamically. It's not user dependent. It's program dependent. I encrypted several tables, then I specified the EXE file to use the encryption. Everything is automatic from there on out. You don't even need the source code. You can also specify that any new file created by the EXE file will also be encrypted. It's amazing! But it's quite expensive. I paid $4900.00 for the developer's version with 55 user licenses.

Check them out at netlib.com