Dolphin Ios-fs Failed To Write New Fst

| Cause | Explanation | |-------|-------------| | Write-protected NAND | The Wii folder in Dolphin’s user directory is set to read-only. | | Corrupt NAND dump | Your virtual Wii NAND (or a custom NAND backup) is damaged. | | Insufficient permissions | Dolphin lacks write access to its own user folder (e.g., installed to Program Files on Windows). | | Antivirus interference | Security software blocks Dolphin from modifying the NAND files. | | Disk full or file locked | The drive is out of space, or another process has a handle on the NAND files. |

The most frequent cause is corrupt or incorrect permissions on your virtual Wii NAND (the internal storage of the emulated Wii). Dolphin has a built-in tool to fix this.

  • Dolphin will scan the NAND. If it finds errors (specifically regarding file permissions or missing directories), it will ask if you want to fix them. Click Yes or Fix.
  • Once finished, restart Dolphin and try the operation again.

    • iOS is aggressive about storage limits. If your device has less than ~500 MB free, Dolphin may not be able to write the FST cache, especially for large dual-layer Wii games (e.g., Super Smash Bros. Brawl, Metroid Prime Trilogy). dolphin ios-fs failed to write new fst

    Navigate to Dolphin’s user directory (by default: Documents\Dolphin Emulator\ on Windows, ~/.dolphin-emu/ on Linux/macOS). Inside, locate the Wii folder.

    The iOS port of Dolphin is not as mature as the desktop versions. Some older builds (especially from early 2023) had known issues with FST caching on iOS. Newer builds have improved filesystem handling. Dolphin will scan the NAND

    Temporary disable real-time protection and test. If the error disappears, add Dolphin’s entire folder to your antivirus exclusion list.

    Writing a new FST often requires temporary space. If your hard drive is full, Dolphin cannot create the temporary index. iOS is aggressive about storage limits

    Dolphin emulator is a powerful tool for playing GameCube and Wii games on PC, but like any complex software, it can sometimes hit unexpected errors. One of the more cryptic messages users encounter is:

    "Dolphin iOS-FS failed to write new FST"

    This error typically appears when launching a game or managing virtual Wii system data. Below, we break down what this error means, why it happens, and how to fix it.