You can connect multi-site Yeastar S-Series VoIP PBX easily by Multisite Interconnect feature.
When you have new voicemail, the Phone tab in the Skype for Business main window displays the number of your messages. See Contact Card opens the caller's contact card, which lists their phone number, email address, office location, and so on. Open Item in Outlook provides more information about the call.

To use a different greeting you already recorded or switch back to the default greeting: On your Android device, open the Voice app . At the top left, tap Menu Settings. In the Voicemail section, tap Voicemail greeting. Next to the greeting you want to use, tap More Set as active.
Finally, and most annoyingly, getting set up with On Voicefeed was pretty tedious. You have to enter basic information, just like almost any other app, which is fine. But then you’re asked to enter a security code that is sent to you by text. At this point, I’m thinking, “Alright, but this better be it.” Then, the app asked me to call a number that was automatically added to my contacts in order to activate the account. Fortunately, that was the end of it, but I was still a little peeved at how long it took to get started. I’m sure that some of those steps are necessary to tap into your voicemail, but finding a way to streamline the process would be much appreciated.