SMG2 uses a streaming audio system that some WAD injectors corrupt. You need an injector that supports "Block IO" and "Audio Streaming" flags.
If you have a softmodded Wii (using LetterBomb or str2hax), WADs allow you to carry your game library on an SD card. You can install Mario Galaxy 2 onto your friend's Wii, play it, and uninstall it without leaving traces. Super Mario Galaxy 2 Wad File
Even though this is a WAD, the error references a disc. This usually happens because your cIOS is outdated. Fix: Update to d2x cIOS v10 beta 52. Ensure you install base IOS 56 into slot 249. SMG2 uses a streaming audio system that some
A WAD (short for Wii Are Dumping or simply a container format) is a package file used by Nintendo’s Wii console for channels—installable software that appears directly on the Wii System Menu. While most retail games are launched from discs, certain titles (like Super Mario Galaxy 2) were never officially released as a downloadable WAD. Important: No official, commercial Wii game was ever
However, unofficial WAD files of Super Mario Galaxy 2 exist primarily for two purposes:
Important: No official, commercial Wii game was ever sold as a WAD via the Wii Shop Channel except for small titles (Virtual Console, WiiWare). Super Mario Galaxy 2 is a full-size DVD game (~4.37 GB) and exceeds the Wii’s internal or SD card channel storage limits without extensive compression.