In order to fix the issue, right-click on the Computer icon, select Manage and open Device Manager. Expand the Network Adapters list, right-click on the driver and select Uninstall. After that, reboot your PC, navigate to Acer Drivers and Manuals web page, identify your laptop model and download the modem driver from the provided list. Next, right-click on the network adapter from Device Manager and select Update Driver Software. Use the Browse option to navigate to the installation package, select the driver and install it following the provided instructions.