I recently purchased a program called Compressed NTFS File Decompressor from download.com

I was getting really annoyed by windows automatically compressing ntfs files behind my back. It was slowing down my computer a lot, especially after doing Windows updates. I didn't realize how much overhead Window's caused on my disk by constantly compressing files. The program helped me out a lot just thought i'd let you all know about it. It basically lets you decompress all NTFS files that are compressed on your hard drive. Good way to speed up your system.

JC

What am I missing here that requires a (commercial) third-party program?

You could have selected the option not to compress when the drive was formatted (as a part of the Windows installation program or anytime later that a drive is formatted).

If you previously selected "compress" (by checking the "compress" box or by default), then consider the following:

If you open Windows Explorer, and right click on any disk drive (a partition of a hard disk) and select "properties" you will find a little box that says "compress". If the box is checked, uncheck it and click "OK" or "Apply". You will be asked whether you want the choice to apply to all subfolders and files. After it gets through uncompressing things that one time, they won't be compressed again.

If it is unchecked and you check it, then when you click "OK" or "Apply" you will be given the option to compress all subfolders also.

If you don't want to compress the entire drive, right click on any folder anywhere and select properties. Click "advanced" and you will see the "compress" box again. Check it or uncheck it, etc.

If performance is more important than disk size, don't compress. If disk size becomes an issue, then compress whatever things that you don't access very often---rarely used applications, backup files, etc. (And consider installing a larger disk drive or, maybe even better, getting rid of stuff that you don't need.)

For example a folder containing CAD system files and projects takes about 325 Megabytes on my Windows XP system. If I compress everything in that directory and subdirectories, the result takes about 308 Megabytes of disk space. So, I might compress the backup copy but not the working copy. (The extra 17 Megabytes isn't terribly important to me on this particular system, so I don't ordinarily compress things. Based on past experience, I believe that compression makes things a little more delicate in case recovery is necessary some time in the future, and I regularly back up user data on external media for safekeeping. The local backup copy is there for convenience.

Regards,

Dave

ok,There are third-party applications which allow you to,
You can visit Qweas which is a website to offer services including software search, downloads and so on.Hope it can help you!