ActiveRoles Server failed to add or remove members from a certain Dynamic Group.
Most likely cause:
The domain controller rejected the request to add or remove objects from the group identified by the "Dynamic Group" field in the event description. A symptom of this condition is the "The directory is busy" or "The server is not operational" error message in the "Details" field of the event description.
What you can try:
Update the membership of the dynamic group by clicking "Rebuild" on the "Members" tab in the "Properties" dialog box for that group, in the Active Roles console.
Alternatively, you might update the membership of all dynamic groups by using the Active Roles console to execute the "Dynamic Group Updater" task located in the "Configuration/Server Configuration/Scheduled Tasks/Builtin" container.