Open an Administrator command prompt and navigate to bin folder in the existing Enterprise Gateway location (example: C:\Program Files (x86)\Symantec\VIP_Enterprise_Gateway\Validation\bin\
Run this command: vsauthremoveserver.exe -servicename vipegLiveUpdateService
Restart the machine.
Open the existing \Program Files (x86)\Symantec) and delete the 9.10 backup (.bak) folder. Do not delete the VIP_Enterprise_Gateway folder.
Open the existing \Program Files (x86)\Symantec\VIP_Enterprise_Gateway\Tools folder and delete healthcheck.wrapper.log and onboarding.wrapper.log.
Attempt the upgrade again.
Note: Removing of the Live Update service is part of the 9.10.1 patch release and already available for Online or Manual upgrade from 9.10 version only.