Current working on cross forest migration between Exchange 2010 and Exchange 2013 I need to share between both Exchange free busy and calendar.
Since Federation is not available (must share smtp domain during migration), I try to share free busy using availability address space.
On source.local and destination.local I run:
add-adpermission -accessrights extendedright -extendendright "ms-Exch-EPI-token-serialization" -user "destination.local- source.local\exchange servers"
Then, add-availabilityaddressspace -forestname destination.local-source.local -accessmethod peruserFB -useseviceaccount:$true
Last, export-autodiscoverconfig -targetforestdomaincontroller dc.destination.local-dc.source.local -targetforestcredential $target -multipleexchangedeployments $true.
Now, I can access to free busy and calendar from source to destination. I can add meetings from source to destination, but from destination to source is not possible (can not access to server).
I have some kind of galsync between forest (exports all source mailbox as contacts on destination using script, but I do some test creating MEU using prepare-moverequest), checked autodiscover on source and destination and seems to be correct.
Try to increase logging but can not find anything on event viewer.
Appreciate any help.