This monitor checks whether the DFS Namespace service could initialize trusted forest information so that client computers can access trusted domains. It does so by looking for the presence of DFS Namespaces event 14550 in the System event log.
An unhealthy state of this monitor indicates that DFS Namespaces could not initialize cross-forest trust information. This can occur for the following reasons:
The forest has only one domain controller
Active Directory Domain Services issues
Check the list of domain controllers
To determine if there is only one domain controller in the forest, open a command prompt window from any computer in the domain and then type Nltest /dclist:<domain> where <domain> is the appropriate domain.
If there is only a single domain controller, add one or more domain controllers to reduce the likelihood of losing the domain if the remaining domain controller fails. Administrators of small networks with only a single domain controller can disable this monitor and ignore the corresponding events in the System event log.
Test network connectivity
To test network connectivity with the affected server, use the following procedure:
1. Open a command prompt window and then use the ping command to check basic network connectivity. If the ping command fails, it is likely that the server is not running, or has network problems that require local access to resolve. If ping is blocked in your network environment, skip this step.
2. If the ping command is successful, test the server’s registration in DNS by using the nslookup command. If the nslookup command fails, there is a problem with DNS. Check the DNS server health or contact the DNS server administrator.
3. If the nslookup command succeeds, it is likely that the shared folder is offline (possibly for maintenance) or there are problems with the permissions on the shared folder.
This monitor resets to a Healthy state after the DFS Namespace service initializes cross forest trust information and it detects DFS Namespaces event 14551.