In order to auto logon on a Windows Server even by a reboot or reset you need to change some settings in the registry. There are many reasons you might need this functionality. For instance; you have an application running on a Windows Server which is only starting or running when a user is logged on.

To enable auto logon for a specific user account follow these steps:

1. Run regedit.exe
2. Navigate to HKLM\Software\Microsoft\Windows NT\CurrentVersion\winlogon
3. Create or edit the following keys:
   AutoAdminLogon ‘1’ (DWORD)
   DefaultUserName ‘username’ (STRING)
   DefaultPassword ‘password’ (STRING)
   DefaultDomainName ‘domain.fqdn’ (STRING)
4. Reboot and Voila!

The only drawback of this method is that your password is readable in clear text in your registry. If that is a huge security risk for some reason, you could consider using Autologon from sysinternals or another application which is doing the same.