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I have two PCs and one micro SD card. What I did was copy some files (1.1 GB) onto micro SD card. But I replaced some files. So everything was perfect, until I tried to use the SD card for Raspberry Pi, when did not work.
I checked the micro SD card again, and most files had disappeared! I connected it to my mac and formatted the micro SD card. It was good for mac but not Ubuntu. It said that 1.1 GB is used! But there are no files.
I re-formatted again, but this time in Ubuntu. And now the total capacity has dropped, and it is unreadable in mac.
Why has this happened? Is there any hope that I can fix it?