Newer releases remove deprecated encryption libraries and improve handshake protocols. This prevents malicious interference during the programming process.
Cause: Windows UAC or folder write restrictions.
Fix: Reinstall KPG99D to C:\KPG99D (not Program Files) and run the app as Administrator every time.
Once you have legitimately acquired the installer:
Step 1: Installation
Step 2: Driver Setup
Step 3: Configuring KPG-99D
Step 4: Reading the Radio