Nintendo Switch 2 blocks online access for using Mig Flash Cartridge

Nintendo is cracking down on Switch 2 users who use a Mig Flash cartridge, a device that lets people play multiple games from a single cartridge by loading them onto a microSD card. Some users have reported that their consoles are permanently blocked from online services, like multiplayer gaming and the eShop, after using this cartridge. The error code 2134-4508 appears, signaling the ban, though offline play still works.

The Mig Flash, also called Mig Switch, mimics a regular Switch game card but can store game backups or pirated copies. While it’s marketed for personal game backups, Nintendo sees it as a piracy tool. Even users who claim they only used legal game copies they own have been banned, suggesting Nintendo can detect the cartridge itself, not just pirated games.

The cartridge’s website warns that online play with unauthorized backups could lead to bans. This issue started soon after the Switch 2 launched on June 5, 2025. A recent Mig Flash update made it work with the new console, but Nintendo quickly responded with bans.

The company has a history of fighting piracy, including lawsuits against those selling similar devices. For now, affected consoles lose online features, but user accounts remain safe. Nintendo’s strict rules aim to protect its system, so Switch 2 owners should avoid using MIG Flash cartridges to stay online.