Back in the days of MS-DOS, many people who needed more storage than they had available used DriveSpace to compress the contents of their hard disk drives transparently. Nowadays, you can get plenty of storage space for cheap, and such compression practice is not required anymore. However, if you are running out of HDD space, and are not willing to spend more money to upgrade, this “transparent compression” will work well to free up your HDD space, and the best tool for the job is CompactGUI.

Typical Windows compression

CompactGUI is mainly a GUI for a command-line program that is already included in Windows. Theoretically, you don’t need CompactGUI to take advantage of Windows’ support for transparent real-time compression. You can right-click on any folder, select “Properties,” and while on the “General” tab, click on the button “Advanced.” From the new window that will pop up, enable the option “Compress contents to save disk space.” Click OK to accept the changes and close the window. Then wait for the compression to complete. Alternatively, you could use the compact tool itself in the command line, which is much more versatile. Compact will offer you access to new, higher levels of compression added to Windows 10, and allow batch-processing of files and folders. But it also comes with some bugs, and if you don’t take care how – or, rather, on which files – you use it, you may render your whole system unusable. Those are the reasons CompactGUI has gotten popular in a short amount of time: it offers the best of both worlds, with none of their shortcomings. Let’s see it in action.

Meet CompactGUI

Visit CompactGUI’s page at GitHub and download it from the link provided in the installation subsection. If you’re using the Chocolatey “package manager” for Windows, you can also install the program by using the command: After the installation completes, run CompactGUI, and we are ready to proceed to the next step.

Basic settings

Click the button with a cog icon on the top right to access the program’s spartan settings. Enable the option “Skip Files that are Poorly Compressed. ” Although this will lead to less than optimal compression, it is worth keeping as doing otherwise would translate to wasted time and resources compressing files that wouldn’t shrink much, if at all. For ease of use, make sure the option “Add to Explorer Right-click Menu” is enabled. This option adds a shortcut to the Windows right-click menu, allowing you to send any folder to the application directly from the Desktop. Leave the rest of the options as they are and exit the window to accept any changes.

Compression levels

Since we already have the program running, drag and drop a game or program’s folder on its window to try out CompactGUI for the first time. The program will update to show you a bunch of options regarding the compression-to-be. On the top left, you will see the four available compression levels. The first one, Xpress 4K, is the lightest and fastest one. The last level, LZX, offers the best compression but is much slower and puts a heavier load on the CPU. In most cases, you can use any of the first three compression levels on any CPU released during the past decade without a significant performance hit. We’d suggest you avoid the last one if you are using an older CPU, or are trying to compress a very resource-heavy program or game. If you feel that the program or game’s performance has deteriorated after the compression, you can always undo the changes by de-compressing it. We suggest you leave the options in the “Select Additional Arguments” section, on the right, as they are. If you decide to tweak them:

“Compress Subfolders” ensures that when you compress a folder, CompactGUI will compress everything in it, and not only the files in its top level.“Force Action on Files” will probably end up wasting your resources by re-compressing files it shouldn’t.“Process Hidden and System Files” will enable the compression of files most people shouldn’t touch, unless they really know what they are doing.“Shutdown PC on Finish” will do precisely that, and from the pull-down menu, you can alternatively select to restart or sleep.

Let’s compress

The final step is a click on the “Compress Folder” button on the bottom right to start the compression. The procedure takes an unpredictable amount of time. It depends on the number and size of a folder’s files, but even more so on their compressibility. CompactGUI also allows you to analyze a folder to check if its contents are already compressed. Leave it for now. That option will become useful when, in the future, you have dozens of folders and you don’t remember which are compressed. After you compress a program or game’s folder with CompactGUI, test how it performs. If there is a visible drop in performance, return to CompactGUI and re-compress it with a lighter but faster algorithm, or fully de-compress it.

Enjoy your expanded HDD

We are way past the DriveSpace era. Transparent compression doesn’t have any significant negative impact anymore in the day-to-day use of our computer and can multiply its storage. Remarkable as that may sound, transparent compression may even lead to increased performance! With storage devices being the primary bottleneck in modern PCs, and CPUs being blazingly fast, most times, compressed files can be loaded way quicker. We can’t guarantee this will be the case for you too. If you spend most of your time playing demanding games that continuously stream data from the hard disks, it would probably be best to avoid compressing them. In most other cases, transparent compression can offer a significant upgrade for minimal impact, so we think, at the very least, you ought to try it out. Read Next:

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