From time to time the CDA Server in scalix can crash and fall into an aborted state. I have seen this happen a lot after power interruptions. If you are using ommaint then you will be notified about it.

What does the CDA Server do?

The Client Directory Access (CDA) Server builds access tables for Scalix directories to provide sorted lists of directory entries.
The Outlook client used with Scalix requires sorted entries in the Address Books. This enables “typedown” functionality when selecting addresses in the interface. The CDA Server is used to provide the sorted lists of directory entries.  

How to resolve:

"service scalix status" shows "CDA Server Aborted"

where "xx" is the instance name (built from first and last letter of the hostname of the server).

# service scalix status (should show started)

(You shouldn't need to but in some cases you may need to force the state of the cda server to off before starting again. Use "omreset -o off cda")