Critical DCOM Authentication Failure (Event ID 10036) – Workgroup Environment (VBR 2022 -> HV 2019)

[mihoo]

I am experiencing a persistent "Access Denied" error when attempting to add/rescan a Hyper-V host from my Veeam Backup & Replication server.

Environment:

VBR Server: Windows Server 2022 (Workgroup)

Hyper-V Host: Windows Server 2019 (Workgroup)

Issue: Event ID 10036 on the Hyper-V host.

Error Detail: "The server-side authentication level policy does not allow the user HOST1\veeam [...] from address 10.100.10.22 to activate DCOM server. Please raise the activation authentication level at least to RPC_C_AUTHN_LEVEL_PKT_INTEGRITY in client application."

Verified Steps Performed:

Registry: Applied RequireIntegrityActivationAuthenticationLevel=0 and ActivationSecurityCheckExempt=1 in HKLM\SOFTWARE\Microsoft\Ole\AppCompat.

Permissions: Granted 'Remote Launch' and 'Remote Activation' rights in dcomcnfg for the service account.

Local Policy: LocalAccountTokenFilterPolicy is set to 1 on both machines.

Connectivity: Verified that WinRM (PowerShell) connectivity from VBR to Hyper-V is fully functional (Enter-PSSession works correctly using the service account credentials via IP).

Request:
The WinRM layer is functional, but DCOM activation is being rejected by the Windows Server hardening policy on the Hyper-V host. Since manual registry/DCOM adjustments failed to bypass the RPC_C_AUTHN_LEVEL_PKT_INTEGRITY requirement, please provide the specific configuration or internal Veeam component adjustment required to force the deployment service to meet these integrity requirements in a non-domain environment.

[david.domask]

Hi Darek,

Sounds like a technical issue, so open a Support case as is required by the forum rules. We cannot meaningfully troubleshoot technical issues over the forums, and topics on technical issues will be removed as per the forum rules.

You might check KB4376, but if it doesn't help, you must open a Support Case as noted above.