When attempting to run an image compliance check against a host or cluster, the task completes with the following error message:
An unexpected error has occurred.
vCenter Server 7.x
vCenter Server 8.x
The cluster image is configured with an ESXi version/build that is later (newer) version/build currently running on the vCenter Server.
For example, the cluster image is configured with a version/build of 8.0 U3 (24022510), and the vCenter Server and ESXi hosts are currently running:
vCenter - 8.0 U1 (21560480)
ESXi hosts - 8.0 U1 (21495797)
The vCenter Server should always be running on the same version/build or newer than the ESXi hosts. The "unexpected error" is due to a compliance check against an ESXi version/build that is a newer version/build from what is currently running on the vCenter Server.
Update the vCenter Server to a version/build that is the same or newer than the version/build configured in the cluster image for remediating the ESXi hosts.
Please see the following KB article for version/build recommendations for vCenter Server and ESXi hosts:
vCenter Server version & ESXi Host version recommendations and considerations