If you read closely, AutoCAD 2015 English has a KB link to Microsoft that is needed:
"The English language versions of AutoCAD 2015 and AutoCAD-based verticals should be installable if you have received the Windows 10 update, KB3081448 or later.
Other AutoCAD language versions and language packs can be installed if Windows 10 update, KB3105210, is applied prior to installation.
DWG TrueView 2015 can be installed if Windows 10 update, KB3105210, is applied prior to installation.
The 2013–2014 versions of AutoCAD products will not be supported on Windows 10."