Scan any .wad file you download (even if you rename it to ISO) with Windows Defender or Malwarebytes before loading it into Dolphin. Malicious code cannot usually escape an emulator, but it can corrupt your save files.
In the context of Wii modding, a WAD is a package format used by Nintendo for installing content to the Wii's internal memory (NAND). For Super Smash Bros. Brawl , users often use forwarder WADs: Forwarder Channels Super Smash Bros.brawl.wad
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