Unhide the hidden folders by some malware activity

Sometimes the removable media connected to a computer with some malware or trojan infects the files and folders in it and it's not possible to unhide them from GUI. This can be done from command prompt:

First open the command prompt as: Start > Run >type cmd
Administrative privileges should be granted for this execution.
Type the command:

attrib -r -s -h I:\* (unhides all the files in I: drive)

attrib -r -s -h "I:\folder_name" /s /d (unhides the folder called folder_name inside I: drive)