If you encounter the publishSelfPresence request error (Error Code = 0-1-492) in the CWA client, you most likely have a problem with the SPN (Service Principal Name) of the CWA Service Account.
To correct this problem; open AdsiEdit and navigate to the CWA Service Account, right click and select Properties.
Scroll down to the servicePrincipalName attribute. The SPN must contain the host name that users are connecting to as well as the physical server. In many scenarios CWA is published as cwa.domain.com while the actual host name may be something like ocscwasrv01.domain.com.
Double click the servicePrincipalName attribute to edit it and make sure both names are registered like this:
Note the single slash, do not type the address as “http://” – and replace host names and domain with your actual values.