Troubleshoot domain-join problems with a Microsoft Entra Domain Services managed domain

When you try to join a virtual machine (VM) or connect an application to a Microsoft Entra Domain Services managed domain, you may get an error that you're unable to do so. To troubleshoot domain-join problems, review at which of the following points you have an issue:

Connectivity issues for domain-join

If the VM can't find the managed domain, there's usually a network connection or configuration issue. Review the following troubleshooting steps to locate and resolve the issue:

  1. Ensure the VM is connected to the same, or a peered, virtual network as the managed domain. If not, the VM can't find and connect to the domain in order to join.
    • If the VM isn't connected to the same virtual network, confirm that the virtual networking peering or VPN connection is Active or Connected to allow the traffic to flow correctly.
  2. Try to ping the domain using the domain name of the managed domain, such as ping
    • If the ping response fails, try to ping the IP addresses for the domain displayed on the overview page in the portal for your managed domain, such as ping
    • If you can successfully ping the IP address but not the domain, DNS may be incorrectly configured. Make sure that you've configured the managed domain DNS servers for the virtual network.
  3. Try flushing the DNS resolver cache on the virtual machine, such as ipconfig /flushdns.

Network Security Group (NSG) configuration

When you create a managed domain, a network security group is also created with the appropriate rules for successful domain operation. If you edit or create additional network security group rules, you may unintentionally block ports required for Domain Services to provide connection and authentication services. These network security group rules can cause issues such as password sync not completing, users not being able to sign in, or domain-join issues.

If you continue to have connection issues, review the following troubleshooting steps:

  1. Check the health status of your managed domain in the Azure portal. If you have an alert for AADDS001, a network security group rule is blocking access.
  2. Review the required ports and network security group rules. Make sure that no network security group rules applied to the VM or virtual network you're connecting from block these network ports.
  3. Once any network security group configuration issues are resolved, the AADDS001 alert disappears from the health page in about 2 hours. With network connectivity now available, try to domain-join the VM again.

If you get a dialog box that asks for credentials to join the managed domain, the VM is able to connect to the domain using the Azure virtual network. The domain-join process fails on authenticating to the domain or authorization to complete the domain-join process using the credentials provides.

To troubleshoot credentials-related issues, review the following troubleshooting steps:

  1. Try using the UPN format to specify credentials, such as Make sure that this UPN is configured correctly in Microsoft Entra ID.
    • The SAMAccountName for your account may be autogenerated if there are multiple users with the same UPN prefix in your tenant or if your UPN prefix is overly long. Therefore, the SAMAccountName format for your account may be different from what you expect or use in your on-premises domain.
  2. Try to use the credentials for a user account that's a part of the managed domain to join VMs to the managed domain.
  3. Make sure that you've enabled password synchronization and waited long enough for the initial password sync to complete.

Next steps

For a deeper understanding of the Active Directory processes as part of the domain-join operation, see Join and authentication issues.

If you still have problems joining your VM to the managed domain, find help and open a support ticket for Microsoft Entra ID.