• A Cloud Foundation upgrade from 3.0 to 3.5 fails with error "The registration of the ESXi upgrade bundle (iso) failed. Upgrade Failed". 
• In the vSphere Web or HTML5 client you see task "Import ESXi Image" with failed status of "The upgrade file already imported and and can be used for upgrades".
• The same ESXi update was successfully applied to one or more ESXi hosts previously.
• You see messages similar to the following in the /var/log/vmware/vcf/lcm/lcm.log file on the SDDC Manager VM:

2018-12-28 16:33:51.504 [lcm,cd1e257fb8392b1b,cd1e257fb8392b1b] [ThreadPoolTaskExecutor-10] ERROR [com.vmware.evo.sddc.lcm.primitive.impl.esx.EsxVumUpdateStageRunnerImpl]  upgradeId=ac9e2fbf-1dab-4a28-bd24-1616e25e1832,resourceType=ESX_HOST,resourceId=3b43ffb2-86d4-4865-a81f-c3783dfc64f7,bundleElementId=4bbbd8b3-6c75-4d48-8ccd-072597204f1d Failed to import upgrade file:com.vmware.vim.binding.integrity.fault.HostUpgradeDuplicatePackage: integrity.fault.HostUpgradeDuplicatePackage.summary
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
        at java.lang.Class.newInstance(Class.java:442)
        at com.vmware.vim.vmomi.core.types.impl.ComplexTypeImpl.newInstance(ComplexTypeImpl.java:174)
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