Changing your Voicemail PIN number
This is another security measure but this time to protect your Voicemail. If you do not set it then someone else could access your Voicemail and listen to your messages or change your personal greeting. Again, we strongly recommend you do this.
Dial 121 followed by SEND , i.e. call your Voicemail.
Key 1 for the main menu then key 42 to access security settings. Then key 2 to set your security code.
There are two levels of security available:
Complete: (you will be prompted for your security code whether accessing messages from your mobile or remotely) key 32.
Standard: (you will be prompted for your security code only when accessing messages remotely) key 33.