• Active Directory / Windows Server 2012

Verify that the domain and forest functional level in Active Directory is Windows Server 2012 or higher.

• You need to be logged in as a domain administrator on a domain controller.

0. Test execution and verification:
1. Go to: Administrative Tools >> Active Directory Users and Computers.
2. In the left pane, right-click the root node for the domain. Then click Properties.
3. In the left span, select the root node and click on Properties in the context menu.
4. The domain functional level and the forest functional level is Windows Server 2012 or higher.

• In case of failure:
• Raise the domain functional level.
• Raise the forest functional level.

0. Solution - Raise the domain functional level
1. Go to: Administrative Tools >> Active Directory Users and Computers.
2. In the left pane, right-click the root node for the domain. Then click Raise domain functional level in the Action menu.
3. Select Windows 2012 or higher from the Select an available domain functional level dropdown box.
4. Click OK.

0. Solution - Raise forest functional level
1. Go to: Administrative Tools >> Active Directory Domains and Trusts.
2. In the left pane, right-click the Active Directory Domains and Trusts node (top element in the tree). Then click Raise Forest Functional Level... in the Action menu.
3. Select Windows 2012 or higher from the Select an available domain functional level dropdown box.
4. Click OK.

HIGH – Kerberos authentication fails

• Raising the functional level cannot be undone.
• Check first if all Windows clients support the higher functional level.