In order to automatically direct a specific caller to your voicemail without your phone ringing, you’ll have to use a different method depending on which phone you’re using.
Great question! Although I don’t know if there is a specific function for this on your particular phone, the best way to save the message is the simplest. Turn up the sound as high as you can and record it onto a digital recorder (like you would use for a lecture), a cassette recorder or your cell phone if you have a voice recorder on it. Then save it as an MP3 on to your computer for safe keeping. You can also Google your vtech model number to see if you can find an owner’s manual. They might have a way to save a recording in there. Probably not, but it’s worth a shot.

You will be asked to delete your current Voicemail greeting. Click on the ‘Yes’ button that appears on the screen if you want to remove that. You can save your new recorded Voicemail greeting or can use the default recorded option. Wait and hear the new Voicemail greeting message that the instructions speak out. If you want to keep that recording as your Voicemail greeting, then save it. Or you can re-record the message to get a different greeting.
4.) Willkommen bei Herrn Mustermann. Herr Mustermann ist gerade nicht am Platz. Bitte hinterlassen Sie eine Nachricht, damit Sie Herr Mustermann so rasch wie möglich zurückrufen kann. Vielen Dank für Ihren Anruf.