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Running FTBU after RUU upgrade is showing this error "The system cannot the file specified"
Within the logs, it is shown that the Core service is unable to detect the Appliance enclosure correctly.
Looking in the disk management, the partitioning of the virtual disk that contains C drive is not typical of how an appliance usually looks like.
A reinstall of OS using normal Windows OS CD/DVD has been performed before this.
It is not supported to perform a reinstall of OS using normal Windows OS CD/DVD.
Performing a factory reset using RASR should resolve this issue.