If you’ve already created a custom voicemail on your iPhone, you can tap Play to see how your voicemail sounds. If you’re interested in creating a new message, tap the Custom button. From here, you can start recording your message by tapping Record and tapping Stop whenever you’re finished. Once you’re finished recording, tap on Play to make sure the message comes across as you’d like and hit Save (in the upper right) to save it as your voicemail.
Apple repairs iPhones at the Genius Bar in Apple Stores and through their online mail-in repair service. Apple repairs are high-quality, but out-of-warranty repairs can be much more expensive than third-party solutions. If you're looking to save some money you're not covered by Apple's warranty, you may want to check out our other recommendations.

You can also delete messages without having to dial into the normal voicemail system. Unfortunately, UK networks have been slow to adopt Visual Voicemail, and it currently just seems to be O2, EE and Orange that offer it to iPhone users. It’s not available from major networks such as 3 and T-Mobile (even though T-Mobile is now owned by EE).
To change your night greeting on a Samsung OfficeServ 100, 500, 7100, 7200 and 7400 phone systems: Press the voicemail button Press * # 0000 Enter the system password Press 1 to edit system prompts Enter 1002 for the Night prompt Press 1 to listen to the current prompt. If this is not the prompt you want to record press * * If this is the correct prompt press 3 to discard the current recording and begin recording a new prompt. Press 2 when finished and review the greeting. If the greeting is acceptable press # to save Hang up