I suspected bad sectors as this is actually more of a Micro-SD card in a usb enclosure+adaptor, and it is a bit old (2+ years). However, when using Disk Genius, i got the report of 100% all good (green) sectors, not even a single yellow, so I am skeptical to say the least. I also recently heard that software like checkdisk and DiskGenius was only designed to scan for sectors on full hard disks, external hard disks, and full SSDs, but not flash memory. I don't know the validity of that comment.
I'm not really looking for big solutions anymore, I'm just curious. Can flash drives/ sd cards be scanned for bad sectors? I'm not interested in the question of its repairability, just whether it can be scanned or not.
If anyone wants to follow up, is there something I may have missed on preventing a drive from going RAW? For conext, I did recently do something to the drive that I do not nornally do, which was insert it to an older backup laptop running windows 7 offline, just for a quick file transfer. That is about the time it happened. But I can't really find out much more about the subject of drives suddenly becomming RAW, specifically how or why it could happen in the first place. also, no viruses, no nalware, no sudden ejects from the system, the card does not have a read-only switch, and I don't remove it from the enclosure.