Yes, you'll have to copy all of the installation files over again, something ain't right with them. If that fails, try a different stick/DVD disc/DVD drive.
True, he might as well get rid of all of them, but let's take this one step at a time instead of overwhelming him.BTW Foxi I think he should delete Partition 3 as well as it's a SWAP partition and it's going to be utterly useless on Windows.
And I suppose that Partition 1 is /boot, which is useless as well and can be safely deleted.