After Recover problem "The relationship between this workstation"

Hello,
I'm not asking for anything that may break the rule of my company or the Froum.
I used to take a full backup from the drive C; for my office's laptop, in case of any problem I can recover.
I was out of the country and got a virus, so I restored my backup and everything working well, when I came back and connected to the Lan at office I got this message whenever I put the log-in password "The relationship between this workstation and the primary domain failed" !!!
and it not allow me to login, until I disconnect the Lan cable.
after I login I plug the cable again and everything working very well, I conneceted to the internet, the shared folders and Lan printer, BUT I notice that the Local Area Connection Icon in the control panel showing the "Domain 2 (unauthenticated)" !!
May I know what happened wrong and why this message appears ? I have administration use for my laptop.
Any suggetions about the that reason caused this message and the effect ? and what is the options to solve it ?

Thank you in advance.