Let me clarify this. If one user can't get online while others can, my first step would be to check the physical connection and ensure that the network cable is securely connected to the user's computer. If the connection is wireless, I would verify that the Wi-Fi is enabled and the correct network is selected. Next, I would check the network settings to ensure that the IP address is being assigned correctly, either automatically or manually, depending on the network configuration. If the issue persists, I would try connecting the user to a different network, such as a mobile hotspot, to rule out any issues with the current network. Additionally, I would check for any software or browser settings that might be blocking the connection, such as a firewall or proxy settings. If needed, I would update or reinstall the network drivers to ensure they are functioning correctly. This systematic approach helps in identifying and resolving the connectivity issue efficiently.