Sometimes it's easy, other times it's not.
Upgrading my old Toshiba L500 to the Anniversary edition of Windows 10 (it's running 1507 right now) hasn't been easy. I lost count of how many times it has made it to 95% and fallen over.
(a) clearing out the upgrade folder and downloading again and...
(b) being patient and...
(c) resetting Win10 (that failed) and rebooting off a fresh Win10 installation USB (which also failed).
I'm no closer to a solution.
I did get a glimmer of hope when I logged in under a different account (I have at least 3 on that box) so I'm backing up - again - after a failed backup and will try all of the above again.
Oh, and I tried to download and run the update manually, too. It failed. And yes, I was logged in as Admin. And made lots of space. And disconnected anything I didn't need.
All good fun.
My other Win 10 boxes - all Lenovos - shamelessly updated effortlessly, by the way. But they are newer, which always helps.