Your phone system greeting is the first thing callers hear. Set the right tone from the very start with professional greetings.
I have a confession to make: I haven’t recorded a new voicemail greeting since 2014. In the past four years, I (hopefully) have become more articulate, poised, and self-assured. But hear my voicemail recording, and you’d think I was still new to the work world, a little unsure of myself — and probably not an authority. Obviously I need toupdate it. And if you haven’t changed your voicemail greeting in over a year, you’re likely in the same boat. After all, a professional voicemail recording boosts your credibility, makes you seem more competent, and encourages whoever’s listening to it to continue the relationship. A relatively unprofessional one — like mine, for instance — does the opposite: It encourages prospects, recruiters, and potential connections to run in the other direction. With that in mind, I’ve written 18 unique voicemail greetings for every situation. Pick your favorite, practice a few times, then record your new voicemail.

Expanding on the simple approach above, let the caller know who they've reached. This will not only eliminate people leaving voicemails by mistake, but it will reassure the caller that they have called the number they intended.
Thank you for calling the XYZ corporation. Please listen carefully to the following menu options, as our menu has recently changed. For new customers, press 1. For existing customers placing a new order, press 2. For product support, press 3. For accounts receivable, press 4. For accounts payable, press 5. To hear contact information and directions to our main facility, press 6. To dial by name, press 7. Press 0 if you wish to reach an operator.