Cluster Aware Updating help

Hi guys,

We are configuring and using Cluster Aware Updating to patch our server 2012 clusters. We triggered the run and it managed to patch the servers but failed to restart them. The error is Failed to restart "server": (ClusterUpdateException) Failed to restart "Server": (Win32Exception) Access is denied

==> (Win32Exception) access is denied.

Any one can help us?

Thank you