Using AVAYA IPO 500 R6 V2 IN 1616 and 1608

i have dhcp on the ipo itself

Depending on which voice mail:
If you are using embedded mail then check connectivity with the line provider or upgrade system.
If you are using voicemail pro on a PC then check network traffic or connect PC directly to the IPO

follow the link it would guide you to configer avaya

http://www.avaya.com/master-usa/en-us/resource/assets/applicationnotes/ipo-ng-vpn.pdf

another link

https://devconnect.avaya.com/public/download/interop/IB-IPAgent.pdf

Various potential network problems might be causing the problem. Access the Network Audio Quality screen. In the event you experience poor audio quality during a call, the problem is likely with your network. This screen provides information that can help identify causes of poor audio quality. Note: Note: The Network Audio Quality button displays only when you are on a call (off-hook). 1. Select Network Audio Quality from the Options Main screen (accessed by pressing the phone's Option button). If administered, the Audio Status screen displays. 2. To return to the first Options Main screen, press the Return softkey.

The solid light on B could be that the handset is offhook.

When a call rings in, the message light can be set to flash as well as the light will flash next to the a (or b ) button that the call is ringing in on.

There is a problem with the trunks. A phone line could be bad, a line (PRI/T1) could be dead....

As you have probably found, SIP phones are not supported until R5, which just came out.

# 2 hang up then #3 hang up

What is your system config? Is there a Professional upgrade license?

The software vpn probably will not work.
Is the vpn tunnel up? Can you ping the IPO? what subnet is the pc?