The Veeem folks explicitly blocked the install on Server2016 because testing with the Tech Preview builds of Windows yielded some “actual issues” with the recovery process.
If you wish to still go forward and use it now, here’s how to get it installed.
In the \EndPoint\Redistr\x64\ folder, sequentially install the database runtimes:
from \EndPoint\EndPoint\, run (as administrator): Veeam_B&R_Endpoint_x64.msi
If you get an error, go through the troubleshooter a time or two until it succeeds. I ran it under the built-in administrator account and had no problems but if you’re logged on as another user (but with admin privs), your mileage may vary.
Update: This is now a 2.0 beta (and renamed to Veeam Client for Windows) that works with Server2016 https://www.veeam.com/download_add_packs/backup-agent-windows/vaw_beta/