Skype for Business users are no longer able to access voicemail messages or change voicemail greetings by dialing 319-467-1660, due to feature changes in Microsoft's Cloud voicemail service. 

Additional information on how to update your Skype for Business voicemail greeting or how to listen to voicemail messages can be found on the Cloud Voicemail Support Center: https://its.uiowa.edu/um.