Sometimes we freak out over every warning message that is displayed when we run Microsoft’s Best Practices Analyzer (BPA). In setting up a new Windows 2012 R2 server recently , BPA displayed a single warning:
Srv.sys should be set to start on demand
The BPA simply says that “Client computers will not be able to access file shares …”
The BPA simply says that “Client computers will not be able to access file shares …”
Wow, that sounds more like a major error waiting to happen! Why, then, is it just a warning?
The answer is that SMB 1.0 protocol is not on by default for Windows Server 2012 R2. SMB 1.0 is required for Windows XP workstations to access file shares.
So you can safely ignore this error.
But, in the chance that you need the SMB 1.0 protocol running, you can do so very easily by opening an elevated command prompt on the server and typing in this command:
sc config srv start=demand
More information is included in this Microsoft Technet article: http://social.technet.microsoft.com/wiki/contents/articles/21104.srv-sys-should-be-set-to-start-on-demand.aspx