I have a Samsung Galaxy Grand with a 16gb micro-sd card. For some inexplicable reason, I am losing data on the sd card. Folder names are being changed to start with the character "μ." For example, my_music was changed to μy_music (this does not happen on the device's internal memory). There are more than 960 files with the name "μ" and it is replicating itself. Is it a problem with the Micro SD card or something else such as the phone itself? Is there any way I can fix this other than formatting?
Check for suspicious applications you may have installed recently. Also this behaviour is very weird as it should usually do that on the internal sd card where it could harm your device and not on the external one where it only annoys the user.
About the "self replicating": If you know in what file the worm is located and checked if all files are the same then deleting that file and formatting your sd card may be the solution to your issue.