Dial-up Connection Error 678 – The remote computer did not respond. To make sure that the server can be reached, ping the remote computer
Dial-up connection error 678 is caused when remote server cannot be reached.. In cellular modem devices, this dial-up error 678 can occur the modem device is not registered with cellular network.
Using AT Command Tester tool, check if device has network service by reading the RSSI value and registration status.
To fix dial-up error 678, retry with a SIM card that can be successfully register with the network. In AT Command Tester tool, check registration status as shown below.
