Hello.
I encounter real difficulties using DSS 7 in our small enterprise environment running under windows server 2012 r2.

I tried everything i know so far but no way to join our active directory. I have the following message :
http://hpics.li/85572d9
What is weird is we have a very heterogeneous network with computers running under windows 7 to 10, MacOS, android devices, printers, synology and qnap nas and each device join the domain without troubles..
the message from dss is very quick, i mean i click apply and less than half a second later i have the fail. So i suppose the message is true : it can not communicate with the domain controller. But if i use the telnet console to ping the DC at 192.168.1.100 there are no packet loss and dss reaches the server...
I have already read (almost) all the checklists regarding obvisous time configuration, security options, firewall, policies and so on...
I am pretty sure the problem is a very very tiny small detail that i did not noticed. But witch one ? i am circumspect...

Some help would be really appreciated.

Thank you ^^
++