I am trying to find a way to block third party (not only ghost) incoming calls,so that they should not be appeared on the screen while i am in a call.
Activating "DND" blocks all incoming calls,how can i manage this?
I am using GS500,running the latest version (220.127.116.11).
this topic was discussed several times in the community. Please use search function and have a look at this PDF.
Use some white/black list on your Firewall (ACL) or even better, buy a Polycom VBP.