Most likely the smtp server that you specified when you set up Outlook Express is the smtp server operated by your home ISP, and maybe they only allow you to send mail through their smtp when you are phsically connected to their access line. You can't send through their smtp server when you're in a hotel--unless they allow relaying by means of authentication. You can use the hotel's smtp server--you need to ask the hotel what is the server address for their smtp server, and then enter that into Outlook Express. Some hotels have networks that intercept your outgoing mail and send it with their smtp server without you making any change to Outlook Express. I don't know if your ISP allows relaying, and if so, I don't understand why your entering the password for your ISP's smtp server only works half the time.