You can find the exact 365 tenant version by performing the steps in the following link:
https://technet.microsoft.com/en-us/library/hh534377(v=exchg.150).aspx#verify
"Official" support is up to and including 15.0.898.9. As far as I can tell it should still function past that but is not supported by TAC.
Also, have you configured the AD user for the mailbox as well (if your 365/ADdeployment is integrated then you probably already have)? Cisco TMSXE supports Office 365-based deployments with both CAS and mailbox servers in the cloud. For all deployments, Active Directory must be on premises in order to work with Cisco TMS, Cisco TMSXE must access the same Active Directory as Cisco TMS.
Have you created the Service User properly?
Creating a Cisco TMSXE Service User in Active Directory In Exchange Management Console, create a new user mailbox as a service user for Cisco TMSXE with the username and password of your choice. The service user will let Cisco TMSXE connect to Exchange and Cisco TMS.
1. In Cisco TMS, go to Administrate Tools > User Administrations > Users.
2. Click New.
3. Add the details for the previously created Cisco TMSXE service user.
4. Permissions in Cisco TMS are controlled on a group level. You must do one of the following: — Add the account to a group with a smaller subset of permissions, see Setting Up Minimal Required Permissions, page 20 below.
— Add the service user to the site administrator group, which has universal access. For each integrated system, the service user must also have the right to book. This is enabled by default for all default user groups in Cisco TMS.
Setting Up Minimal Required Permissions In order for Cisco TMSXE to be able to book endpoints and access booking information from Cisco TMS, you must make the service user a site administrator or a member of a group that has the following permissions:
■ Read and Book under Systems > Navigator > Select a system > Folder and System Permissions > System Permissions.
■ Read under Systems > Navigator > Select a folder > Folder and System Permissions > Folder Permissions for all the folders above the system in Cisco TMS folder structure.
To view and/or modify the permissions for a Cisco TMS user group:
1. Go to Administrative Tools > User Administration > Groups.
2. Hover over the group you want, click the drop-down arrow and select Set Permissions.
3. Under Booking, make sure enabled permissions include: —
List Conferences - All
• Read
• Update — Misc
• Booking
• Book on behalf of
• Approve Meeting
4. Click Save if any modifications have been made.
The Cisco TMSXE server must: be configured to use a DNS server with service records for the Active Directory domain of the Exchange server, and have network access to Active Directory, meaning no firewall must be blocking traffic, and LDAP and Global Catalog must be open. The communication will be authenticated using the Cisco TMSXE Exchange service user account
