In addition to their actual content, files also have a set of properties that characterize them (sometimes called metadata.) One set of these properties are the four attributes read-only, hidden, system, and archive.
The archive attribute is primarily used in backup procedures but the other three can be encountered in various contexts. These attributes can be turned on or off with the command “attrib” and its switches.
The great utility of this command is that it can act on subfolders with its switch “/s” and can use the wildcard “*”.
For example, to clear the read-only , system, and hidden attributes from a file use
attrib -r -s -h somefile
This operation is not uncommon when system files have to be edited.
To restore the attributes the command is
attrib +r +s +h somefile
A common situation where it is desirable to clear the read-only attribute from many files is when files are copied from a CD. By default CD files are normally marked read-only. This can interfere with editing.
To clear the read-only attribute from all files in a folder and its subfolders use
attrib -r somefolder\*.* /s
If you want to process all files of a certain type such as MP3, use
attrib -r somefolder\*.mp3 /s