I'm experiencing the exact same issue no matter how I try to update the server. If I try to export to a folder and update from a USB thumb drive, or if I try to download directly via FTP.
If the LifeCycle Controller Enhanced is not at a required minimum revision for compatibility with files it may result in the above error. You will need to update the LCE for it to recognize the files. There are links to the latest updates at the bottom of this knowledge base article. Please follow the instructions and update in the proper order:
Dell EMC, Enterprise Engineer
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