Symptoms:
While trying to add a standalone host with VMware vSphere ESXi version higher than 7.0 U2a and lower than ESXi 7.0 U3c, trying to associate an image with this host is prevented.
During the addition of a host to vCenter a version check is performed when the host is being managed with vLCM. The add host is prevented if any version between 7.0 U2a and ESXi 7.0 U3c is installed.
vCenter Server Add Standalone Host Failure Notification UI:
To resolve the issue, upgrade the VMware vSphere ESXi host version to a version higher than ESXi 7.0 U3c and then try to add the host to be managed with an image.