One of the customers was using the Azure file PVs created manually on OCP 4.10 where PV mount was working on windows nodes. After upgrading the OCp version to OCP 4.12, Azure file PV is failing with below error:
~~~
Events:
  Type     Reason       Age                  From               Message
  ----     ------       ----                 ----               -------
  Normal   Scheduled    2m40s                default-scheduler  Successfully assigned ocp-project-sbc/winapp-fileshare-app-abc to windows-node-abc
  Warning  FailedMount  37s                  kubelet            Unable to attach or mount volumes: unmounted volumes=[volfile], unattached volumes=[volfile kube-api-access-ngx7x]: timed out waiting for the condition
  Warning  FailedMount  32s (x9 over 2m40s)  kubelet            MountVolume.MountDevice failed for volume "pv-abc" : kubernetes.io/csi: attacher.MountDevice failed to create newCsiDriverClient: driver name file.csi.azure.com not found in the list of registered CSI drivers
~~~

In this case, PV is provisioned following documentation: https://docs.openshift.com/container-platform/4.12/storage/persistent_storage/persistent-storage-azure-file.html#create-azure-file-secret_persistent-storage-azure-file.

PVC:
~~~
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
    pv.kubernetes.io/bind-completed: "yes"
  creationTimestamp: "2023-07-18T10:13:12Z"
  finalizers:
  - kubernetes.io/pvc-protection
  name: pvc-abc
  namespace: ocp-project-abc
spec:
  accessModes:
  - ReadWriteMany
  resources:
    requests:
      storage: 10Gi
  volumeMode: Filesystem
  volumeName: pv-abc
status:
  accessModes:
  - ReadWriteMany
  capacity:
    storage: 10Gi
  phase: Bound
~~~

PV:
~~~
apiVersion: v1
kind: PersistentVolume
metadata:
  annotations:
    pv.kubernetes.io/bound-by-controller: "yes"
  creationTimestamp: "2023-07-18T10:12:53Z"
  finalizers:
  - kubernetes.io/pv-protection
  name: pv-abc
spec:
  accessModes:
  - ReadWriteMany
  azureFile:
    secretName: stacnt-devapps-fileshare
    secretNamespace: null
    shareName: abcfileshare
  capacity:
    storage: 10Gi
  claimRef:
    apiVersion: v1
    kind: PersistentVolumeClaim
    name: pvc-abc
    namespace: ocp-project-abc
  persistentVolumeReclaimPolicy: Retain
  volumeMode: Filesystem
status:
  phase: Bound
~~~

SC:
~~~
NAME              PROVISIONER                RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
azurefile-csi     file.csi.azure.com         Delete          Immediate              true                   25d
managed-csi       disk.csi.azure.com         Delete          WaitForFirstConsumer   true                   348d
managed-premium   kubernetes.io/azure-disk   Delete          WaitForFirstConsumer   true                   348d
~~~

Here, event error shows CSI driver registration error but PV and PVC are not related to csi driver and it is type of in tree storage. 

OCP 4.12.19

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Mount is failing with CSI related error where its searching for registered CSI drivers. But windows nodes only support in tree storage and not CSI.
Ref: 
- https://docs.openshift.com/container-platform/4.12/windows_containers/windows-containers-release-notes-7-x.html#windows-containers-release-notes-limitations_windows-containers-release-notes
- https://github.com/openshift/enhancements/blob/master/enhancements/windows-containers/csi-proxy.md

On OCP 4.12, application pods should mount the Azure file PVs created manually(non-csi) on windows nodes.