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CISER Computing User's Manual: Compressing Files Using NTFS

Compressing your files using NTFS

About NTFS

All CISER computing systems have a NTFS compression utility.

  • NTFS compressed data can be used in its compressed state by most software packages on the research servers.
  • You may encounter an error when compressing very large files.
  • NTFS compressed files are platform depentant. If moved to a different computer, files will NOT be copied in their compressed state.
  • NTFS compressed files have their filenames shown in blue font on the research servers.

Compressing files

  1. Open the folder where you have the file(s) you want to compress.
  2. Highlight the file(s) you want to compress. While still highlighted, right-click on them and choose Properties. Select the General tab, and see how the bytes for Size and Size on disk are not very different.  more...
  1. Click on the Advanced... button.
  2. Check the Compress contents to save disk space box, and click OKmore...
  1. Back in the Properties window, click Apply. Notice how the bytes for size on disk has significantly decreased. Click OKmore...

User notes:

  • If you want all the files within a folder to be compressed, you can right-click on the folder name instead of a file name.

  • Although this utility appears to allow you to use compressed files with software packages as if the files weren't compressed, what's actually happening is that the system is uncompressing the file each time you use it, and re-compressing it when done. If you plan to work on a compressed file more than one time per session, it would be beneficial to both you and the system for you to manually uncompress the file, work on it, and then manually re-compress it before logging off. This will save both your time and the system's resources.

  • For files larger than 4 GB, there is some loss of stability and reliability when using Windows NTFS compressed files with SAS and other applications. If your file is very large, please uncompress it before using it and then re-compress it when your done.

  • Additional information about Windows NTFS Compression may be found at: