imapd、popd 和 httpd 問題的徵兆

連線被拒絕或系統速度太慢而無法連線。例如，如果未執行 IMAP 並且您嘗試直接連線至 IMAP，您將看到如下訊息：

telnet 0 143 Trying 0.0.0.0... telnet: Unable to connect to remote host: Connection refused

如果您嘗試與用戶端連線，您將收到以下訊息：

Client is unable to connect to the server at the location you have specified. The server may be down or busy.