Same problem here since yesterday.
Server displays "Virus signature database could not be updated" & "An error occurred while downloading update files" and won't connect to the Remote Administrator.
Windoes Server 2008 R2 Standard. Eset File Security version 4.5.12011, stuck on database 12288. Server hasn't been touched for a while so I can't see what would have changed out of the blue yesterday.
Also when I check License Validity I get "License could not be verified. Please enable access to the expiration database server expire.eset.com" but I can still access the web through a browser OK.
I've tried clearing update cache, pre-release updates, etc, but still broken.