COMPACT
Displays or alters the compression of files on NTFS partitions.

COMPACT [/C | /U] [/S[:dir]] [/A] [/I] [/F] [/Q] [filename [...]]

/C Compresses the specified files. Directories will be marked
so that files added afterward will be compressed.
 

/U Uncompresses the specified files. Directories will be marked
so that files added afterward will not be compressed.
 

/S Performs the specified operation on files in the given
directory and all subdirectories. Default "dir" is the
current directory.
 

/A Displays files with the hidden or system attributes. These
files are omitted by default.
 

/I Continues performing the specified operation even after errors
have occurred. By default, COMPACT stops when an error is
encountered.
 

/F Forces the compress operation on all specified files, even
those which are already compressed. Already-compressed files
are skipped by default.
 

/Q Reports only the most essential information.
filename Specifies a pattern, file, or directory.

Used without parameters, COMPACT displays the compression state of
the current directory and any files it contains. You may use multiple
filenames and wildcards. You must put spaces between multiple
parameters.