If you are seeing a "Checksum Error" or "Corrupt Archive" message for this specific part, you can try the following steps to fix it without redownloading the entire set: 🛠️ Common Fixes for Archive Errors

If using Steam, right-click the game > Properties > Installed Files > Verify integrity of game files .

Sometimes WinRAR throws errors that 7-Zip can bypass. Try right-clicking the .part01.rar file and selecting "Extract files..." using 7-Zip.

If you are downloading parts individually via a browser, using a download manager with multiple connections can sometimes cause corruption. Try redownloading part 15 using a single-connection setting. 💡 Game Launch Issues

Check your antivirus history to see if it blocked u4.exe or tll.exe . Adding an exception for the game folder often fixes "failed to save" or launch errors.