[Q]Strange folder : .eCtcQjbu1dgnvtFnvnr6yepTp1M= topic

Hello, I would like to ask if somboby know for what is : .eCtcQjbu1dgnvtFnvnr6yepTp1M= folder in internnal memory and SD Card?

Also, I have problem with some images....you can see the attached file....the files are brocken and not usable.(all those images are only on SD card)? What si this problem with SD Card?

I'm not sure if we have connections between the 2 questions.

Thank you in advance.