Downloaded photos from Samsung Galaxy S7 are corrupted on PC but viewed OK from Android Gallery after the internal storage got full

I have a Samsung Galaxy S7 Edge on Android 6.0. I usually take videos and photos and then get a message from the Camera app that I can't use the app anymore since my phone memory/RAM is full. I usually connect the phone to a PC and then download and delete the photos from the phone, and it's back running fine. The last time when it was full, I noticed it was going to take forever to transfer. I checked the phone's DCIM Camera folder and noticed some 8GB JPEG images. Strange, and I thought they were created while I was "shooting video" and the phone may have been low on space already, and I was hitting that PHOTO button during video shooting to also get some photos during the video shooting. Interestingly, in the Windows folder preview, I could even see a small "preview" of the actual JPEG image even though it was 8GB in size supposedly, but I could not "open it", may have complained of RAM or some other issue can't remember. I also noticed there were some files that had corrupted file names like: 2018Ȱ620_160140, basically after the "2018", some kind of strange mark above O. The issue/complaint is, well I can't really remember for "sure" if even the 8GB file photos displayed perfectly fine on my phone, but all the others that I at least know for sure looked all great on the phone but were *corrupt* if I tried to view them on my computer. It didn't matter if I viewed the version I copied to my computer, *or* if I viewed it on PC directly from my phone. The phone does not use any SD card, only the built-in RAM/memory it came with, etc. I just retried everything with a different USB cable, no difference. I had also rebooted the phone in case anyone wondered, made no difference. Why are my photos all being corrupted when I transfer/copy them to my computer?