Regular maintenance is critical for keeping your organization’s PCs running smoothly, and end users can play a significant role in this process when properly trained. For years, support professionals have been showing users how to delete their temporary Internet files and clean out their temp folder. But often users were shown how to perform these tasks manually instead of using Windows Disk Cleanup. Disk Cleanup determines which files on a hard drive may no longer be needed and deletes those files, freeing up a potentially significant amount of space.

Starting Disk Cleanup
Disk Cleanup is available on Windows 98/Me/2000/XP and some later editions of Windows 95. To start Disk Cleanup, click Start | Programs | Accessories | System Tools | Disk Cleanup. You will then be prompted to choose the particular drive you want to clean up. Once you do, Disk Cleanup will analyze the selected drive and determine the amount of space it can free up. One thing to remember: This analysis may take several minutes, so be patient.

Disk Cleanup then presents you a list of the file categories it can clean up (see Figure A).

Figure A
Disk Cleanup identifies file types that may no longer be needed. This screen shot is from a computer running Windows XP.

Fortunately, Disk Cleanup doesn’t automatically begin erasing files without giving you a chance to see what will be removed. You might have noticed the View Files button in Figure A. If you select one of the cleanup options and click this button, Disk Cleanup will show you the files it plans to delete. In the list of files to be deleted, if you see items that you want to keep, you can either skip cleaning up that file category altogether or you can move those files to a safe location prior to proceeding with the cleanup process. Then, when you’re ready to begin the cleanup process simply click OK.

Targeted file categories
Now that you know how Disk Cleanup works, lets look at various file categories that Disk Cleanup targets.

Downloaded Program Files
You probably think of downloaded program files as applications, in the form of ZIP or EXE files, downloaded from the Internet. However, Disk Cleanup categorizes downloaded program files as ActiveX controls and Java applets downloaded from certain Web sites and temporarily stored in the Downloaded Program Files folder. So it’s safe to keep this option selected.

Temporary Internet Files
This refers to Internet Explorer’s cache of Web pages. Selecting the Temporary Internet Files option is almost always safe to use since things like cookies aren’t included in the mix.

Recycle Bin
The Recycle Bin option cleans out the Recycle Bin for the selected partition. Remember that each partition has its own individual Recycle Bin. Although it’s usually safe to clean out the Recycle Bin, I recommend going through the files before deleting them. You may be surprised at what you find in there.

Temporary Remote Desktop Files
The temporary remote desktop files are created when Remote Desktop is used. To enhance Remote Desktop performance, some files, such as wallpaper and icons are copied from the remote machine to the host machine. If you rarely use Remote Desktop, it’s probably safe to remove these files. However, if you frequently use Remote Desktop to connect to the same computer or to the same group of computers, you’re probably better off leaving these files alone. You won’t hurt anything if you decide to erase them, but you’ll temporarily slow Remote Desktop’s performance since the files will have to be recopied.

Setup Log Files
The Setup log files don’t really consume all that much space, but you can get rid of them if your system has been up and running fine for a while and you no longer care about what happened during Setup. On my test system, the Setup log files consumed about 800 KB of space.

Backup Files For Previous Operating System
If you’ve upgraded to Windows XP from a previous operating system, Setup will attempt to create a backup copy of your previous operating system. This consumes a lot of disk space. The core operating system files are backed up, as well as drivers and icons. In fact, so many files are backed up, that on my system, the backup files for the Windows 98 operating system consume about half a gigabyte of disk space.

Offline Files
Offline files tend to exist on laptops more often than on desktop machines. For example, to prepare for a recent meeting during which I knew I wouldn’t have Internet access, I made several Web sites available offline. This process consumed several gigabytes of hard drive space. After my meeting, I forgot about the sites until the next time that I ran Disk Cleanup.

The More Options tab
While most of the cleansing options are on the Disk Cleanup tab, you shouldn’t ignore the More Options tab, shown in Figure B. This tab contains additional processes Disk Cleanup can perform to free up disk space.

Figure B
This screen shot of the More Options tab is from a computer running Windows XP.

These processes will be different depending on which version of Windows you are running. Under Windows 98, for example, you have three options: Windows Components, Installed Programs, and Drive Conversion (FAT32). Under Windows 2000, you are only given Windows Components and Installed Programs. Windows XP’s version of Disk Cleanup again offers you three choices: Windows Components, Installed Programs, and System Restore. Since I would never recommend that the average end user perform a drive conversion, I’ll skip this option and only discuss the other options.

The Settings tab

If the computer is running Windows 98, you will see a Settings tab alongside the Disk Cleanup and More Options tabs. This tab allows you to configure Disk Cleanup to run automatically if the drive runs low on disk space. I recommend disabling this option because it may confuse end users to have Disk Cleanup pop up without warning. Instead, teach your users to practice routine disk maintenance to keep their hard drives uncluttered.

Clicking the Cleanup button in the Windows Components section launches the Windows Components wizard. From there, you can select or deselect check boxes to set what you want to be installed within Windows. Keep in mind that initially, the wizard shows you only categories, not individual applications. So I recommend drilling down by selecting a category and clicking the Details button and selecting or deselecting applications on an individual basis.

Clicking the Cleanup button in the Installed Programs section opens the Add/Remove Programs dialog box. You can remove any currently installed program by selecting it and then clicking the Change/Remove button. Windows will then take you through the removal process. Unlike the Windows Component Wizard, which allows you to remove batches of Windows components, the Add/Remove Programs dialog box requires you to remove applications one at a time.

Clicking the Cleanup button in the System Restore button opens a dialog box that asks you if you’re sure that you want to delete all but the most recent restore point. Clicking Yes begins the cleanup process.

After the cleanup
Disk Cleanup can reclaim a big chunk of disk space. After cleaning up my test system, I was able to reclaim just under 2 GB of space (mostly because of offline files, an old operating system, and temporary files). One item to note: Getting rid of a lot of files tends to leave gaps of empty space on your hard disk. I strongly recommend that you defragment your hard disk after you run the cleanup.