First Log in to your server. Within the server follow these steps:

Step 1:

Click Search, type 'run'  then click on Run.

Step 2:

In the Open box, type Regedt32.exe, and then press OK.

Step 3:

Locate the following subkey in the registry:

Step 4:

Right click on the field -> New -> String Value

Type DefaultUserName and press enter

Double-click the DefaultUserName entry, type Administrator, and then click OK.

Right click on the field -> New -> String Value

Type DefaultPassword and press enter

Double-click the DefaultPassword entry, type your password that you use to login to the server and then click OK. 

 

Right click on the field -> New -> String Value

Type AutoAdminLogon and press enter

Double-click AutoAdminLogon. In the Edit String dialog box, type 1 and then click OK.

Exit Registry Editor.

Now your automatic Logon is enabled. Whenever you reboot the server, the windows user will automatically log in.