2025-05-02T10:34:37.213Z In(05) vcpu-0 - Guest: [ warning] [vmvss:vmvss] [1096] CVmSnapshotRequestor::CheckWriterStatus():2489: writer Registry Writer in failed state: res = 0x800423f4, err = 0x1, error =
2025-05-02T10:34:37.213Z In(05) vcpu-0 - Guest: [ debug] [vmvss:vmvss] [1096] CVmSnapshotRequestor::CheckWriterStatus():2501: Registry Writer (9)
2025-05-02T10:34:37.213Z In(05) vcpu-0 - Guest: [ debug] [vmvss:vmvss] [1096] CVmSnapshotRequestor::LogComponentError():802: enter
2025-05-02T10:34:37.214Z In(05) vcpu-0 - Guest: [ debug] [vmvss:vmvss] [1096] CVmSnapshotRequestor::LogComponentError():837: failed call: ret = compEx2->GetFailure(&writerErr, &appErr, &appMessage, NULL), resu
lt = 0x80070057
2025-05-02T10:34:48.488Z In(05) vcpu-1 - Guest: [ debug] [vmvss:vmvss] [1096] CVmSnapshotRequestor::UnregisterProviderImpl():2952: Provider unregistered.
2025-05-02T10:34:48.488Z In(05) vcpu-1 - Guest: [ debug] [vmvss:vmvss] [1096] CVmSnapshotRequestor::RequestorThread():1766: exit result: 0x80042301
2025-05-02T10:34:48.651Z In(05) vcpu-1 - Guest: [debug] [vmbackup] *** VmBackupAsyncCallback
2025-05-02T10:34:48.652Z In(05) vcpu-1 - Guest: [debug] [vmbackup] *** VmBackupPostProcessCurrentOp
2025-05-02T10:34:48.652Z In(05) vcpu-1 - Guest: [debug] [vmbackup] VmBackupPostProcessCurrentOp: checking VssSyncStart
2025-05-02T10:34:48.652Z In(05) vcpu-1 - Guest: [debug] [vmbackup] *** VmVssBackupOpQuery
2025-05-02T10:34:48.652Z In(05) vcpu-1 - Guest: [debug] [vmbackup] *** CVmVssRequestor::QueryStatus
2025-05-02T10:34:48.667Z In(05) vcpu-2 - Guest: [ debug] [vmvss:vmvss] [1596] CVmSnapshotRequestor::QueryStatus():1678: enter
2025-05-02T10:34:48.667Z In(05) vcpu-2 - Guest: [ debug] [vmvss:vmvss] [1596] CVmSnapshotRequestor::NeedWaitForSnapshotCompleted():1344: enter
2025-05-02T10:34:48.668Z In(05) vcpu-0 - Guest: [message] [vmbackup] Snapshot operation error: IDispatch error #8449 (0x80042301)
2025-05-02T10:34:48.668Z In(05) vcpu-0 - Guest: [debug] [vmbackup] *** VmBackup_SendEventNoAbort
2025-05-02T10:34:48.668Z In(05) vcpu-0 - Guest: [debug] [vmbackup] Sending vmbackup event: vmbackup.eventSet req.error 5 'VssSyncStart' operation failed: IDispatch error #8449 (0x80042301)
2025-05-02T10:34:48.668Z In(05) vcpu-0 - Guest: [debug] [vmsvc] RpcChannel: Sending: 98 bytes
2025-05-02T10:34:48.668Z In(05) vcpu-0 - Guest: [debug] [vmsvc] VSockChan: Sending request for conn 616, reqLen=98
2025-05-02T10:34:48.669Z In(05) vmx - Msg_Post: Warning
2025-05-02T10:34:48.669Z In(05) vmx - [msg.snapshot.quiesce.vmerr] The guest OS has reported an error during quiescing.
2025-05-02T10:34:48.669Z In(05)+ vmx - The error code was: 5
2025-05-02T10:34:48.669Z In(05)+ vmx - The error message was: 'VssSyncStart' operation failed: IDispatch error #8449 (0x80042301)
2025-05-02T10:34:48.669Z In(05) vmx - ----------------------------------------
2025-05-02T10:34:48.670Z In(05) vmx - ToolsBackup: changing quiesce state: FINISHING -> ERROR_WAIT
In the windows application logs the below error is seen
"A VSS writer has rejected an event with error 0x800423f4, The writer experienced a non-retriable error. If the backup process is retried,
the error is likely to reoccur.
. Changes that the writer made to the writer components while handling the event will not be available to the requester. Check the event log for related events from the application hosting the VSS writer.
Operation:
Freeze Event
Context:
Execution Context: Writer
Writer Class Id: {afbab4a2-367d-4d15-a586-xxxxxxxx}
Writer Name: Registry Writer
Writer Instance ID: {1575f88a-f188-4e7f-aa28-xxxxxxxx}
Command Line: C:\Windows\system32\vssvc.exe
Process ID: 4596"
VMware vSphere Esxi(All Versions)
When Windows Server Backup initiates a backup of a disk volume within a virtual machine, a Volume Shadow Copy (VSS) snapshot is triggered for the targeted volume. During snapshot creation, all associated VSS writers for that volume are invoked. If any of the VSS writers report an error or fail, the entire backup operation
It is recommended to involve Microsoft Support to further investigate the errors reported by the VSS writers.