Look into snapRAID. It does parity based data protection (up to 6 I believe). It’s free, opensource. I use it to run a nightly sync and scrub of ~3% of my total disk space, so in a month it scrubs everything to protect against bit rot. It then shoots me a nightly email with any errors or issues it detects. There is a learning curve, but I’m happy to provide some basic scripts for you to get it running in Windows. You can also run it on top of pooling solution such as Drivepool.