Summary:

In CRM there is the ability to add resources to appointments. Resources can also be set up in Exchange.  

When creating an appointment if a resource’s email address matches a resource in Exchange it will sync with CRM the same as any user set to sync. 

The only difference is that resources do not appear in the list of users to be selected for Exchange synchronisation. They will sync as standard when the Exchange Integration is set up and working.

Status:

This has been addressed and fixed in all of the recent patches of 7.1 and 7.2

More information:

There is a known issue with some older 7.1 and 7.2 patches that caused this functionality to not work.  If your resources are not included in the sync and it is valid please check your current CRM version and apply the latest patch if required.