Mysterious files showing up in file explorer

Running Win 10 anniversary update on new HP all-in-one with a 256GB SSD (C:) and a 2TB SATA (D:) drive. About three weeks ago I decided to move all of my data files from C: to the D: drive leaving only OS and program files on C:. I did not permanently delete Documents, Music, Pictures and Video folders from the C: drive. Everything seems to be running fine but I've noticed that in file explorer I keep having random files mysteriously appearing in This PC (current example: in the Documents folder I now have a subfolder named "Adates191" and another named "Bstorage59"). They both contain a bunch of Word, Excel, txt and other weird files that cannot be opened. I also have a file named "astores60" and "xsettingssettings11" in my Windows (C:) list, again contain crappy files like my previous example. Finally, in my Data (D:) drive I have two new files "Cversion36" and "Whelper148" with the same gibberish as above. If I delete all of them some different ones mysteryiously replace them. What in the world have I done to myself that could have caused this? HELP!!!!!!!!!!!!!

Do they have an extension what is file size. Are your doc's etc OK I am wondering if you have Ransome ware encrypting files

Pretty sure you have a virus. If you use an Anti-virus program like Avast, run a thorough scan. If not . . . get one. Windows Defender is getting better but the main line programs are excellent. There are lots of comparative reviews on Google. Never install a program before scanning it with your anti-virus and never - ever - turn off the anti-virus while installing a program.

Also, watch carefully while you install a program. Many come with extra goodies which need to be rejected or they will install with the desired program. They may or may not be viruses but if you want one, look it up first.

A scan with AdwCleaner would likely help too. It doesn't require installing, just download and run.
Malwarebytes | AdwCleaner

Thanks, everyone for your input and suggestions. I believe I found the culprit. It's a ransomware app ironically called "Ransomfree." See https://www.cybereason.com/ for details. I tried it at the suggestion of a friend since I recently deleted Spybot Search & Destroy because I could not update to the current version and I wanted to have at least 2 malware tools on hand. He claimed that he uses it because it doesn't require repeated scans, updates, etc. The site looked legit enough so I added it. I was not prepared for the crazy stuff it was doing to file explorer and didn't see it was this app that was apparently causing it. I deleted it and the weird stuff stopped and everything seems back to normal! So, I consider this one solved. In addition to Malwarebytes I have McAfee A/V suite and also do regular scans with MS Malicious Software Removal Tool. I'll give AdwCleaner a try to fill the gap of my second scanning tool. Thanks, again, for the prompt response and suggestions!!