Network connection problem
Check whether the local network connection is normal, including the connection between the local computer and the router, the connection between the router and the public network, and the connection between the public network and the station server. You can try to use other network environment or replace the network equipment to solve the problem.
Firewall issues
Check the firewall settings of the local computer and the site server, such as Windows Firewall, security software, etc., to ensure that they can be accessed properly. Also, you need to check the security group settings of the site server to prevent it from being mistaken as an attack and being blocked.
User name and password problem
Confirm whether the remote login account and password are correct, if you forget the password you can solve it by resetting the password.
Hardware failure problem
If there is no problem with the above points, then there may be a hardware failure on the site server itself, which requires further inspection and repair.