Despite the silly name, AOMEI Backupper is a program I have used a lot recently with great success. It's very similar to Acronis Backup, back when Acronis was actually useful and not unreliable bloatware

It's free, although there is a paid version that does more. The main difference seems to be that they moved the drive clone function to the paid one a couple of versions ago. You can achieve the same result but it's a two step process now, without some of the bells and/or whistles.

If you want that function you need to find V3.5, but for just doing differential backups, the current free one works well. It can be scheduled, it's easy to set up, so far seems to be reliable to me, and yes, I've tested the backups by restoring them!

Just so you have another data point. I came across it by accident when I was rebuilding my machine after a problem that ultimately turned out to be the fault of the SoftPerfect Ramdisk program, and got very frustrated with how incredibly slow Acronis was.

pca