Dial prompt error 720: Unable to establish a connection to the remote computer.

The connection error 720 is caused by an incorrect network protocol, and the solution is as follows:

1. Right-click the computer and select Manage;

2. Click Device Manager;

3. Uninstall "WAN Miniport(IP)" in "Network Adapter" in device management and restart the computer. At this time, the problem of computer network connection error 720 is solved.