My laptop shows that it is connected to the internet, but webpages and videos either buffer indefinitely or take an extremely long time to load. Gmail eventually opens, but it can take nearly an hour. I disabled the built-in Wi-Fi adapter, tried a separate USB Wi-Fi dongle, and connected through Ethernet, but the problem stayed the same. Windows reports that the connection is stable, and other laptops on the same home network work normally. I also tested a phone hotspot and public Wi-Fi with the same result. I have already tried a network reset, removing VPNs, reinstalling and updating the network drivers, and several command-line network resets. What else should I check before reinstalling Windows?
4 Answers
Since the issue follows the laptop across your home Wi-Fi, Ethernet, a phone hotspot, and public Wi-Fi, the router and internet provider are probably not the main problem. Try checking for an enabled proxy, custom DNS setting, security software, or another background program interfering with traffic. Also compare the behavior in Windows Safe Mode with Networking or from a temporary Linux USB. If the connection works there, the problem is likely with Windows or an installed application.
The standard resets are worth trying from an administrator PowerShell window: run `netsh winsock reset`, `netsh int ip reset`, and `ipconfig /flushdns`, then restart the laptop. Also check Windows Update and the laptop manufacturer's support page for network drivers, chipset drivers, and BIOS updates. Make sure you restart after installing anything.
Booting from a Linux live USB is a useful way to separate hardware from Windows problems without changing the installation. If browsing works normally in Linux, back up your files and consider repairing or clean-installing Windows. If it is still slow there, check for hardware problems such as a failing SSD, overheating, or another system component causing the laptop to stall.
Before doing a factory reset, open Command Prompt and run `ipconfig /all` while the problem is happening. Check whether the laptop has a normal IP address, gateway, and DNS servers. You can also try temporarily setting DNS to a reliable public service such as 1.1.1.1 or 8.8.8.8, though the fact that the problem occurs on several networks suggests DNS may not be the only issue.

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