Error messages like ‘import failed’, ‘connection failed’ and ‘connection time out’, the possible reasons are listed as follows:
1, Bad network condition. We can test the network by ‘Ping’ command.
2, Check whether the management port/server port has been opened if you want to add the device via WAN IP.
3, Incorrect user name or password.
4, IP address or Mac address is locked. We need to confirm with administrator.