The "Failed to save data" error in Prototype 2 is a well-documented issue often caused by modern Windows security settings, permission conflicts, or hardware incompatibilities
Prototype 2 runs via Proton, but save issues arise due to Linux file system differences. prototype 2 failed to save data fix
If you share a minimal code example (save call + model shape + error messages or network response), I can produce a targeted fix and patch you can drop into your code. The "Failed to save data" error in Prototype
Windows sometimes "virtualizes" saves for older games, placing them in a hidden AppData folder instead of your actual Documents. Here is how to force the correct behavior. Here is how to force the correct behavior
Prototype 2 was developed for older operating systems and may struggle with standard user permissions in Windows 10/11.
Windows’ ransomware protection often blocks older games.