Hello! Recently I've noticed above mentioned error on our company server. We have installed Nod32 Business edition 188.8.131.52 with mirror enabled. The license has been renewed 2 weeks ago and it's valid ( as stated in the program ), but when it comes to updating, it starts updating and on some 50% i get that invalid usn/pass error. What is interesting, when i delete all the files in mirror, it updates normally without any problem. I tried reinstalling but it's not helping, and i can't really restart the server so often since it's our domain controller and also all the internet traffic goes trough it. Any help would be appreciated.