Issue with adding RD Session Host Server to Collection - Error Event ID: 12306

Question

I am encountering an issue when attempting to add a Session Host to a collection in Remote Desktop Services.:

Unable to retrieve the session collection properties. Some or all identity could not be translated.

To ensure synchronization of the RDS database, we have removed and re-added all related security groups, but the issue persists.

Interestingly, we are able to successfully add the same Session Host to a newly created collection.

Thank you for your assistance.

Answer 1

Dear Team,

The issue with Event ID 12306 and error "Unable to retrieve the session collection properties. Some or all identity could not be translated" usually means a broken or missing SID (Security Identifier) in the existing collection. This commonly happens when:

A user or group previously added to the collection was deleted or renamed.

The RDS configuration database is referencing a non-existent SID.

AD replication or permission mismatch exists.

Why it works in a new collection: The new collection doesn't reference the broken SID(s), so it avoids the error.

Option 1 (Best Fix): Recreate the collection. Since the Session Host works fine in a new one, migrate your users and settings to the new collection.

Option 2 (Advanced): Manually fix the broken SID in WMI / RDS configuration database:

Open PowerShell as Administrator

1. Run:
2. Get-WmiObject -Namespace "Root\RDMS" -Class Win32_RDMSDeploymentSettings
3. Or use SQL Management Studio if you are using a central SQL deployment to query rds.configurationsessions and remove broken SID entries manually.

Option 3: Check group memberships and AD synchronization. Make sure all users/groups still exist and are resolvable in AD.

Best Regards,