To record an IVR greeting sound file:

• Navigate to 'Settings: Access Codes' and make sure that '*301' is set under 'Greetings'
• Dial '*301' from your extension and speak into the microphone after the tone.

• 1 - Accept the message
• 2 - Listen to your message
• 3 - Re-record the message

Only after you press 1 your greeting message will be recorded.

• The recorded sound file should be saved under 'greeting-$DATE.gsm' name
• Edit the IVR and select 'greeting-$DATE.gsm' under 'Greeting' option
• Click 'Save'

Now every call that comes into this IVR will play your custom greeting message.