TechDuke

One of the many advantages of choosing the NTFS file system over FAT32 is that it offers slick and essentially seamless on-the-fly compression. To compress a file (or an entire folder) stored on an NTFS-formatted volume, all you have to do is set an attribute for that object; Windows decompresses the file or folder automatically when you access it.

To compress a file or folder, right-click its icon in Windows Explorer, choose Properties from the shortcut menu, and click the Advanced button on the General tab. In the Advanced Attributes dialog box, select Compress Contents To Save Disk Space.

To compress an entire volume at once, right-click the drive icon in Windows Explorer and follow the same procedure. You’ll be asked to confirm that you really want to do this for every file in the volume. When you say yes, the system begins compressing files, one at a time. The process can take hours to complete; fortunately, it only needs to be done once. You can continue working while Windows is busy compressing files. If the system needs to compress an open file, you’ll be notified with a dialog box. At that point, you can close the file in question and click Retry, or click Ignore or Ignore All.

TIP
When you select the encryption option, the compression button in the Advanced Attributes dialog box is cleared.
For security and performance reasons, encryption and compression are mutually exclusive attributes for files stored on an NTFS volume If the fi le is compressed, it can’t be encrypted, and vice versa If you need to combine compression with security, consider using password-protected Zip files, which offer good (but not great) encryption along with efficient compression capabilities Use the third-party WinZip program (http://www.winzip.com) or the Compressed Folders feature in Windows.

When you compress a folder, that attribute affects files that you move or copy later, according
to the following rules:

+ If you create a new file in a compressed folder, the new file is compressed.

+ If you copy a file into a compressed folder, the file is compressed.

+ If you move a file from a different NTFS volume into a compressed folder, the file is compressed.

+ If you move a file into a compressed folder on the same NTFS volume, the file retains whatever compression setting it had originally; in other words, its compression attribute remains unchanged.

+ If you move a compressed file into an uncompressed folder on the same NTFS volume, the file retains the compressed attribute. However, if you move a compressed file to an uncompressed folder on a different NTFS partition, the file loses the compression attribute.