Hard Drive Maintenance Procedures

Of all of the devices inside your computer, the hard drive is the single device that requires the most maintenance. It is in constant bidirectional communication with the CPU, saving data and retrieving data. The magnetic platters inside the hard drive are in almost-continual spinning motion, and the read/write head flutters quickly over the platter surface.

Over time, the hard disk is subjected to a number of CPU processes that modify and add all sorts of data that is stored on the drive.

There are several maintenance procedures with which you should be familiar, which we can clarify by describing some of the problems that can occur.

When you surf the Internet, pages are cached (temporarily stored) on your hard drive. Temporary folders and files are often created when you download files from the Internet and extract them onto your hard drive. These folders and files can remain on your hard drive, taking up more and more space, until you remove them.

Temporary files may also be created when you work with a word processor, spreadsheet, or other application. The ‘working’ copy is usually saved as a temporary file, and while it should be deleted when you save the file and exit the program, it sometimes is not. After some time, your hard drive becomes unnecessarily cluttered.

Further, when you first create and save a data file on a new hard drive, the file is saved in contiguous blocks or sectors on the drive. Eventually the hard drive becomes more filled up with data and/or applications. Subsequently, new data files, or files which become larger in size as you work on them at a later date, are split up into pieces, and these file chunks are stored wherever there is available space.

The fragmentation of these files creates a couple of problems. One is that it will take longer for the file to be opened, as the file fragments have to be reassembled before the file can be opened. More importantly, file fragmentation creates more wear and tear on the drive, as the read/write head is forced to move back and forth across the spinning platter searching for and retrieving the file fragments.

There may also be software programs/applications installed on your computer that you are no longer using. Removing programs which you no longer need can free up significant space on your drive.

Yet another problem is that the magnetic surface of the platters (or disks) inside the hard drive can deteriorate and break down over time, rendering some sectors unreliable. Unless these bad sectors are identified and flagged, it’s possible for you to save data that will not be able to be retrieved later on.

Fortunately, there are solutions to all of these problems. The solutions should be implemented in a certain order. For example, you would not want to defragment the drive before eliminating all the junk temp files. What you want to do is get rid of the file clutter first, not simply move them to a new location and then still have to delete them.

So here’s the recommended order of events:

  1. Delete temporary Internet files (cached web pages)
  2. Delete temp files and programs no longer needed
  3. Run Scandisk or Check Disk (aka ‘Error Checking’)
  4. Defragment the hard drive

So the first step is to clear out the temporary Internet files – copies of web pages that you’ve visited that have been saved for faster viewing. Over time, these pages can take up quite a bit of space on the hard drive.

Here’s the procedure as it would be done using Windows Internet Explorer in Windows Vista:

  1. Open your Internet browser.
  2. Click on ‘Tools’ and select ‘Internet Options’
  3. Under the General tab, in the ‘Browsing history’ section, click the ‘Delete’ button
  4. In the ‘Temporary Internet Files’ section, click on the ‘Delete files’ button

You may also notice that there is another section in the same window, just below Temporary Internet Files, called ‘Cookies’. These can also be safely deleted, but before you do, let’s clarify what cookies are and what purpose they serve.

Contrary to popular perception, cookies are not applications that collect any personal information about you from your computer, track your browsing history, and so forth. Rather, they are small text files that are created when you visit a web site and create a profile of some sort.

A data file, known as a ‘cookie’ is then created and stored on your computer which will allow the web site to store such things as your name, address, passwords, email address, login information, and so forth.

When you revisit that web site and see some of your profile information pre-filled in, it’s because a cookie has been retrieved from your drive. If you delete your cookies, you will have to recreate your profile information.

The downside to cookies is that completing online forms with your personal information can lead to receiving unwanted solicitations for products, services, etc.

You’ll have to weigh for yourself the costs/benefits of storing cookies on your computer. You can also modify the cookie settings on your computer by opening ‘Internet Options’ as described above, selecting the ‘Privacy’ tab. You can adjust the settings to anywhere within the range of accepting all cookies to blocking all cookies.

The second step is to remove temp files and old software programs that are no longer being used. These temporary files are created when you install applications, or when you use certain applications like Microsoft Word (whose AutoSave feature causes ‘temp’ files to be created, which are not always deleted upon exit).

Because these temp files can be scattered in various locations across the drive, they can be difficult to find manually. Luckily, there is a handy utility available through Control Panel that will help you locate and remove temp files, a variety of unneeded system files and software programs, and will also empty out the Recycle Bin. This will both free up disk space and help your computer to run faster.

Here’s what to do in Windows Vista:

  1. Click the Start button
  2. Select ‘Control Panel’
  3. Select ‘System and Maintenance’
  4. Under ‘Administrative Tools’, click on ‘Free Up Disk Space’
  5. In the Disk Cleanup Options window, you may choose ‘My files only’ or ‘Files from all users on this computer’ (if you want to remove old software applications, you must choose the latter).
  6. Follow the prompts for Drive Selection and choose what files you want to remove
  7. Select the More Options tab if you wish to remove unneeded software programs

Once the temp files and unneeded programs have been deleted, you can proceed to the drive maintenance utilities. As is often the case, the particular names of these drive utilities depends upon the version of Windows you are using.

Until the release of Windows XP and later versions, the program designed to identify bad sectors on the drive was called Scandisk. This was readily available in the Accessories folder (Start > Programs > Accessories > System Tools > Scandisk).

When you run Scandisk, it will identify the bad sectors on the hard drive, attempt to repair them, and flag those sectors as non-writeable if they cannot be repaired. In this way, your data will be protected, as it will only be saved to reliable sectors on the drive.

In later versions of Windows, the utility has been renamed (Checkdisk, or chkdsk for short, identified with the label ‘Error Checking’), but it serves the same purpose. To access this feature in Windows Vista, follow these steps:

  1. Go to Start > Computer
  2. Right click on the drive you want to check (usually this is Local Drive C:)
  3. Select ‘Properties’ from the menu list
  4. Select the ‘Tools’ tab
  5. Click the ‘Check Now’ button in the Error-Checking section
  6. You have two options. Select ‘Automatically fix file system errors’ and additionally you may select the other option as well ‘Scan for and attempt recovery of bad sectors’

Let the utility run to completion, which can take some time. The time taken by these repair utilities is generally directly proportional to the data storage capacity of your hard drive. That is, the larger the drive, the longer it’s going to take to scan it, defrag it, run a virus check on it, and so forth.

You may have noticed that just below the ‘Check Now’ button for Error Checking, there is a section and a button called ‘Defragmentation’. Once the Error Checking utility has been run to completion, you should defragment your drive.

Defragmenting your drive will rejoin files that have become split up over time, and will also consolidate all the free space on the drive into contiguous sectors. Because data will be moved to other areas of the drive, it’s critical that the sectors onto which data is relocated are known good sectors. For this reason, you should always run Check Disk (or ScanDisk) BEFORE you defragment your drive.

Defragmentation is a process that can take several hours, again depending upon how much data you have stored on the drive and how large the storage capacity of the drive is.

How often should these utilities be run? It really depends on how much you use your computer. A reasonable minimal interval would be about once a month. However, if you use your computer extensively, you should run them more frequently. Try to get on a schedule so you don’t forget about these important maintenance tasks.

An important point worth mentioning is that despite your greatest efforts to cleanup your computer, it’s impossible to remove every bit of clutter, and eventually there will be a buildup of miscellaneous junk – stray files and folders, references in the Windows Registry that point to programs no longer installed on the computer, and so forth.

Ultimately, the only way to get rid of this junk is to begin with a fresh slate – by formatting the drive and reinstalling everything from scratch. Professionals recommend this be done yearly. Remember that formatting the drive will destroy data, so you will need to back up your data, and be sure to have on hand your operating system installation CD as well as installation CDs for all your software applications and programs.