Pen drive show empty even when data exists | Empty Pen drive but showing Space consumed

First of all check if the files are not in hidden mode :

Folder and search option  --> Show hidden Iteams.

If not work Try :

Click on "Start" -->Run --> Type cmd and press Enter. 

 I assume your pendrive drive letter as E: 

Enter this command. 

attrib -h -r -s /s /d E:\*.* --> Press Enter 

You can copy the above command --> Right-click in the Command Prompt and 

paste it. 

Note : Replace the letter g with your pen drive letter. 

Now open pen-drive it will show your data.