Decompress All The Files in A Hard Drive

To decompress all NTFS-compressed files on a Windows drive, open Command Prompt and move to the root of the drive first. For example, for drive C::

C:
compact /u /s /a /q /i

What the command does:

• compact manages NTFS file compression.
• /u uncompresses compressed files.
• /s applies the operation to files in the current directory and all subdirectories.
• /a includes hidden and system files.
• /q uses quiet mode and prints less output.
• /i continues even if errors occur.

Repeat the same pattern for any other drive by switching to that drive first:

D:
compact /u /s /a /q /i

Run Command Prompt as Administrator if the drive contains protected system directories or files owned by other users. The process can take a long time on large drives, and decompressed files may require significantly more disk space, so check free space before running it.