This article helps you to troubleshoot issues when Update Manager is unable to stage patches to an ESX/ESXi host.
Failed to import upgrade. Error was: failed upload
<YYYY-MM-DD>T<time> ['HostUpgradeMetadata' 3456 ERROR] [metadata, 796] Can not read MD5 checksums, error: ios_base::failbit set
<YYYY-MM-DD>T<time> ['HostUpgradeMetadata' 3456 ERROR] [metadata, 834] Cannot process MD5 checksums in cosless upgrade package, error: integrity.fault.HostUpgradeChecksumFailure
<YYYY-MM-DD>T<time> ['HostUpgradeMetadata' 3456 ERROR] [metadata, 894] Integrity verification of upgrade package failed.
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