Today, I feel like Bill Murray in the movie Groundhog Day. While working with a customer on a Lync pilot, I ran into an issue where Users on the Lync Pool could not see Presence for Users on any other Pool. The user would see “Presence Unknown” for all Contacts on Pools other than their own as shown below:
This was a little bit different than the last time I saw the issue. This time the Users couldn’t see Presence for existing Contacts. This only impacted Users on other Pools though, not Users who were homed on the same Pool.
After a quick email exchange the customer removed the policy “Configure SIP compression mode” that had been set to “Based on ping round-trip time” as shown below:
After the policy was removed users could see presence for all contacts again:
I have reported this issue to Microsoft and hopefully the KB published last time will be updated to include Lync.
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