In the former, the voicemail message shall be delivered to callers from within your company i.e. for communication exclusively for office employees. In the second case, the voicemail will be received by people calling from outside the company. Hi. You’ve reached Martha Johnson in Human Resource department. Unfortunately, I cannot attend the call now. You can leave your message after the beep. Hello. You’ve reached Martha Johnson in Human Resource department. You can either record your message after the beep or contact my secretary Henry Smith at extension 5556. I shall get back to you soon.
If they don’t leave a message, you’ll never know who called. Some people may assume they should just call back later. But if you prefer to get back to them at your leisure, encourage them to leave a message.

If you only check and return messages once a day or once a week, let your caller know. This will avoid multiple messages by the same caller.
Creating a professional voicemail greeting isn’t complicated, but you need to keep a few things in mind to ensure success. The following tips will help: Be friendly and welcoming - let your company's personality shine!; Have a clear voice, speak at a slow to moderate pace, minimize background noise; Ensure the greeting is human and approachable; Keep the greeting short and informative; Ensure the greeting doesn’t sound robotic or unnatural; Show your gratitude for the call by saying thank you; Manage expectations by clearly stating when the client can expect a callback.