I use 820, and the memory card is 16G. My friend tried it on an Android phone, used my memory card and plugged it in. The pixels of the original photo became smaller.

It is possible that the data is damaged, the card reader can't read it, and the food stops completely.

This situation is nothing new, and sometimes it does happen when the data card is accidentally uninstalled. Read it again with a card reader or Android phone. It's best to read it. Back up the data, format the memory card, and then import the content.

If you can't read it, you will be in big trouble. You can only use hard disk recovery tools to recover it.

The material of sd is a bit special. If it is a hardware recovery, it will take about a week to recover. The success rate is almost 100%.

If you use the software downloaded from the internet to recover, the time is very fast, about a few hours, but the success rate is low, about 50%. It is estimated that some photos will be damaged and cannot be read. The sd card repaired by software cannot be repaired. Further data corruption may occur,