13.故障現象：計算機屏幕上出現“The Modem is being used by another Dial-up Networding connection or another program。Disconnect the other connection or close the program,and then try again” 的提示框。
分析、排除：檢查是否有另一個程序在使用調制解調器；檢查調制解調器與端口是否有沖突。
14.故障現象：計算機屏幕上出現“The computer you are dialing into is not answering。Try again later”的提示框。
分析、排除：電話系統故障或線路忙，過一會兒再撥。
15.故障現象：計算機屏幕上出現“Connection to xx.xx.xx. was terminated. Do you want to reconnect?” 的提示框。
分析、排除：電話線路中斷使撥號連接軟件與ISP主機的連接被中斷，過一會重試。
16.故障現象：計算機屏幕上出現“The computer is not receiving a response from the Modem. Check that the Modem is plugged in,and if necessary,turn the Modem off ,and then turn it back on” 的提示框。
22.故障現象：計算機屏幕上出現“A network error occurred unable to connect to server (TCP Error：No router to host)The server may be down or unreadchable。Try connectin gagain later” 的提示時。
