Polycom HDX or GROUP: SIP/2.0 409 Conflict: publication version out of date
You will not be able making call to Lync Clients. SIP/2.0 409 Conflict
Error on the Client side might be:
"call was not completed or has ended"
"video was not accepted"
You might also see in the SIP protocol that the Polycom System is communication with itself in the FROM and TO Header.
Reboot the HDX or GROUP, due to deleting the Cache on the conferencing System
(Beside, this only applies if you had the HDX/ GROUP working before)
Author: Thomas Pött Managing Consultant Microsoft UC