IS-FC05: Couldn't verify hash serialization

This error occurs when you have a valid file and file size but the file’s hash value is incorrect. This can happen when your hard drive uses an incorrect file system to install your game or your computer has faulty RAM.

Verify your hard drives are using the NTFS file system

Follow these steps to check the file system that your hard drive(s) are using:

1. Click Start.
2. Type This PC and press Enter.
3. Right-click your hard drive and select Properties.
4. Check the File system field.
   • If this says NTFS, you’re using the correct file system.
   • If this says FAT32, you’ll need to convert the hard drive to NTFS with the help of this Microsoft article: Overview of Disk Management

Perform hard drive test

Hard drives sometimes have errors that can be resolved by checking them using CHKDSK. Follow these steps to check your hard drive:

1. Click Start.
2. Type cmd.
3. Right-click Command Prompt and select Run as Administrator.
4. Type chkdsk c: /r /f and press Enter.
   Note: You can run this command for any hard drive by replacing c: with d:, e:, etc.
5. Press Y and then Enter to allow your hard drive to be checked when you restart your computer.
6. Restart your computer.

Note: You only need to restart if you check the hard drive your operating system is running on. This process may take some time to complete. If you receive any errors, your computer should repair these during the process. Once this is complete, try to install your game again.

Perform memory test

If you're still seeing the error, you may have bad RAM in your computer. Try performing a memory test within Windows to determine whether you need to replace your memory:

1. Click Start.
2. Type Windows Memory Diagnostic and press Enter.
3. Select Restart Now and check for problems.

If any errors are found, you’ll need to replace your memory and try installing your game again afterward.