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- Alex -

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What type of files are on your hard drive?

Every day you create and delete files on your computer, install and remove programs that add and remove files, copy files, rename files, etc. You have tens of thousands of files on your hard drive. After a basic clean installation of Windows 98, you'll already have well over 2000 files. To see how many files you have right now, open up Windows Explorer by going to Start/Programs/Windows Explorer. Click once on your hard drive in the left column. Now hit Ctrl-A on your keyboard, which will highlight all files and folders on the right. Then right-click on the highlighted files and select Properties from the menu. In the resulting window, you'll see at the top the number of files. More than you thought, isn't it?

Now if you take a look at the list of files on the right, you'll see rows of folder icons, followed by rows of file icons. Each file has its own unique name, since you cannot have two files with the same name in the same folder. If you're looking at the root directory of your C: drive, you'll probably see a few file names such as Autoexec, Command, etc. Some others might have pretty cryptic names such as RG2CATDB or SFCSYNC. But what does that mean and what do those files do? Read on if you're curious what files there are, what they do and how to identify them easily.


When you install Windows and then open Windows Explorer, you won't see much. By default, Windows hides a lot of information about your files as well as dozens of files from you to reduce the risk of your operating system being compromised by your messing around with them. But since we're the curious type, let's change a few settings so we can start looking behind the scenes.

After installing Windows, the very first thing I do is open Windows Explorer, go to View/(Folder) Options (Tools/Folder Options in Windows 2000) and select the View tab. Here you'll see a list of radio buttons and check boxes. The first one I modify is labeled Hide file extensions for known file types. Uncheck it. The next one we're interested in is the section labeled Hidden files. Select the radio button Show all files. That's all we're doing here for now, so click OK. When you're back to the Explorer window, go to the View menu and select Details. Now look at the list of files and folders on the right. It should look a lot different now.

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