IS-BV05: Build verification failed due to file size mismatch

This error can be caused by your hard drive using the incorrect file system required to install your game or bad memory.

Verify your hard drives are using the NTFS file system

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

1. Click on Start.
2. Type This PC and press Enter.
3. Right-click on your hard drive and click on Properties.
4. The file system will be listed under the Type. 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. To do this do the following:
   1. Click on Start.
   2. Type cmd and press CTRL+SHIFT+ENTER.
   3. Type convert C: /FS:NTFS and press Enter. (Make sure to type the appropriate drive letter depending on what it is on their computer.) This process may take a while depending on the size of your hard drive.

Perform memory test

This error is a sign that you may have bad RAM in your computer. You should perform a memory test within Windows to determine if you need to replace your memory.

1. Click on 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 afterwards.

Turn on Memory Integrity

Memory Integrity can help prevent other software from affecting your computer. To turn this on check out the Microsoft Support article: Device Protection in Windows Security

Once this has been turned on try installing you game once again.