A user connects to the companys intranet server via a VPN connection from a small office / home office （SOHO） using the broadband service. One day， the user cannot successfully connect to the VPN and receives an error message that states "Username and password are invalid on the domain." Which of the following should be done to correct this problem？（）

• A、Call the corporate help desk to have the VPN server rebooted
• B、Re-enter the username and password in the VPN connection and reconnect
• C、Call the broadband Internet provider to replace the SOHO router with a newer model
• D、Ping the corporate VPN server to ensure it is online