当我尝试发送/接收电子邮件时，SIM800L GSM模块始终响应：+ POP3IN：62（表示DNS解析错误）
这里可能有什么问题？
我尝试了3种不同的服务提供商，3种不同的电子邮件服务器，以及2种不同固件的SIM800模块。
请在此处查看命令历史记录： history
20.08.2017 16:03:24.15 [TX] - AT+CREG?
20.08.2017 16:03:24.17 [RX] -
+CREG: 0,1
OK
20.08.2017 16:04:07.01 [TX] - AT+CGATT?
20.08.2017 16:04:07.03 [RX] -
+CGATTT: 1
OK
20.08.2017 16:04:26.98 [TX] - AT+SAPBR=3,1,"CONTYPE","GPRS"
20.08.2017 16:04:27.02 [RX] -
OK
20.08.2017 16:04:29.37 [TX] - AT+SAPBR=3,1,"APN","internet"
20.08.2017 16:04:29.40 [RX] -
OK
20.08.2017 16:04:39.69 [TX] - AT+SAPBR=1,1
20.08.2017 16:04:40.36 [RX] -
OK
20.08.2017 16:04:42.78 [TX] - AT+SAPBR=2,1
20.08.2017 16:04:42.80 [RX] -
+SAPBR: 1,1,"10.142.235.73"
OK
20.08.2017 16:04:47.32 [TX] - AT+EMAILCID=1
20.08.2017 16:04:47.35 [RX] -
OK
20.08.2017 16:04:48.43 [TX] - AT+EMAILTO=30
20.08.2017 16:04:48.45 [RX] -
OK
20.08.2017 16:04:53.42 [TX] -AT+POP3SRV="mail.baumtronics.com","xxx@baumtronics.com","",110
20.08.2017 16:04:53.46 [RX] -
OK
20.08.2017 16:05:07.55 [TX] - AT+EMAILSSL?
20.08.2017 16:05:07.57 [RX] -
+EEMAILSSL: 0
OK
20.08.2017 16:05:14.70 [TX] - AT+POP3IN
20.08.2017 16:05:14.72 [RX] -
OK
20.08.2017 16:05:15.74 [RX] -
+POP3IN: 62
20.08.2017 16:06:04.97 [TX] - AT+POP3SRV="s10-london.accountservergroup.com","xxx@baumtronics.com","xxx",995
20.08.2017 16:06:05.03 [RX] -
OK
20.08.2017 16:06:16.86 [TX] - AT+EMAILSSL=1
20.08.2017 16:06:16.87 [RX] -
OK
20.08.2017 16:06:20.76 [TX] - AT+POP3IN
20.08.2017 16:06:20.77 [RX] -
OK
20.08.2017 16:06:21.52 [RX] -
+POP3IN: 62