As normally we can't see administrator account in welcome screen, however we can open it on startup screen by pressing Ctrl+Alt+Del two times. But we can permanently add administrator account to welcome screen too, follow these steps:
- Go to start> run> Type regedit
- Go to the path HKEY_LOCAL_MACHINE\ SOFTWARE\ Microsoft\ Windows NT\ CurrentVersion\ Winlogon\ SpecialAccounts\ UserList
- Right-click an empty space in the right pane.
- Select New> DWORD Value Name the new value Administrator. Double-click this new value, and enter 1 as it's Value data.
- Close the registry editor and restart your system.