Paid MSDN subscribers can download virtually every Windows build ever released, including 1511. If you are a developer or IT pro with access, this is the safest route.
Windows 10 Version 1511 (Build 10586), also known as the November Update or codename "Threshold 2," windows 10 version 1511 build 10586 iso
10586 Version Name: 1511 (Codename: Threshold 2) Release Date: November 2015 Paid MSDN subscribers can download virtually every Windows
After installing Windows 10 1511, you will face immediate challenges because the build is out of support. windows 10 version 1511 build 10586 iso