We're using a hybrid Exchange 2016 setup with Exchange Online.
In some meetings we can see that some people's freebusy is not available.
Me (opening the meeting), and the recipients for which it doesn't show are all located in EXO.
* Outlook cached mode : some recipients freebusy is unavailable.
* Outlook online mode : working perfectly (all freebusy can be viewed)
* OWA EXO ; working perfectly (all freebusy can be viewed)
I tried recreating the Outlook profile (cached) > Issue still occurs
I tried removing the recipient cache for these recipients > Issue still occurs
Some thing to notice is that the 3 recipients for which I can't see the freebusy, immediately show as not possible to request.
For the other recipients, it takes some time to be requested and it shows correctly
X500 address is ok, and didn't change