File disappear after unzipped by 7 Z.

I just got my Dell Computer today, was trying to install back all the file.   I tried to unzipped some dat files by using 7 z, the dat files were successfully unzipped but it "disappear" in the folder.    I can see the dat file in 7 Z list, but it doesn't show up on my computer folder, I've googled and realized some people experience the same issue, the cmd method on youtube doesn't work for me.

Is it Window 10's fault??  I've tried it with another brand computer (with Window 10), and got no problem with it.    7 Z never fail me in the old days, so is it Dell computer issue?  I tried to restart my computer, didn't work at all.      I really need help!  It's a big 25GB dat file and it's wasting my space but not showing up.