I specifically created an account on this site to chime in and thank everyone for their time and comments. A windows 10 system I built for a client was repeatedly failing the Anniv update at 23%, backing out, and causing my client constant grief that he continued to blame me for. After pulling a WD passport USB 3.0 backup drive he had along with the optical drive SATA cable, the update cruised right through with no issues. Old thread here I know but thanks again and hope this helps others here in 2017 and beyond!