If a Switch system update fails, start by checking your internet connection—use a wired Ethernet adapter for stability, or move closer to the router. Free up storage space: delete unused games or files to ensure at least 1GB of free space, as insufficient storage causes updates to fail. Restart the Switch by holding the power button for 15 seconds, then try the update again. Download the update manually from Nintendo’s website: transfer the file to a microSD card, insert it into the Switch, and enter Maintenance Mode (hold power + volume up + volume down) to apply the update. Check if the router is blocking Nintendo’s servers—temporarily disable firewalls or parental controls. If manual update fails, contact Nintendo Support—they can guide you through advanced steps or repair the console if there’s a hardware issue.