Found the problem, and more important, the solution (or workaround). Reading this article https://www.veeam.com/kb1597
, I have added my notebook user (that is from different domain of Veeam server) to Veeam users group of server, but this not worked for me. Then I tried to run my ONE client with server users with runas command, and magically it is connected !
In brief, from my notebook: runas /user:domain\user monitor.exe (where domain\user is the Veeam server user).
Could you investigate about this behavior ?