No free/busy information could be retrieved. The recipient’s server could not be determined. Contact your administrator.
Issue: Unable to see Free / Busy information of partner domain users in Cross-forest topologies.
Error: No information. No free/busy information could be retrieved. The recipient’s server could not be determined. Contact your administrator.
Recently I have integrated Exchange Free/ Busy information between Exchange 2007 SP2 and Exchange 2010 SP2. Already extended availability address space, extended the ad permission with access rights however unable see Free / Busy information.
Steps to configure Free / Busy information. Use below URL to configure Free/ Busy information for Cross-Forest Topologies.
Use below steps to troubleshoot Free/ Busy information.
1. Verify the availability address space and see required SMTP domain with access method.
2. Check availability (EWS) URL from both forest on exchange CAS server.
If EWS URL must be accessible.
3. Still unable see Free / Busy information.
4. Using TMG for publishing OWA and outlook anywhere. In TMG using Basic authentication and same Basic authentication for Outlook Anywhere.
5. Look like issue because of Basic Authentication on TMG level.
6. Later Bypass the TMG.
7. Free / busy started working after bypassing the TMG.
8. Later changed the permission on TMG level for Outlook Anywhere rule to pass through and Free / Busy stared working as expected.