Carrying on from my earlier entries.
My system uses Win 8 and Win 7 Dual Boot.
Both partitions are on the same disk.
Win8 is the first partition on the drive and is the master boot partition, but I still had error code 0x80004005.
I copied the Win8 partition to another disk and removed dual boot.
I downloaded Win8.1 from scratch but still got the 0x80004005 error.
I think I am going to give up on Win8.1 unless Microsoft can come up with a fix.