How to Safely Clear Temp, %Temp%, and Prefetch Files in Windows

As you use your Windows computer, your operating system and applications create temporary files to store data for short-term use. Windows also creates "prefetch" files to help your most-used programs launch faster.

Over time, these files can accumulate, taking up valuable disk space and sometimes even causing minor performance issues. Cleaning them out is a great piece of digital housekeeping.

This guide will show you two safe methods to clear these files and reclaim your storage.

What Are Temp and Prefetch Files?

Before we start deleting, let's quickly understand what we're clearing:

• %temp% (User Temp): This is a folder (located at C:\Users\[YourUsername]\AppData\Local\Temp) where your user-specific applications store their temporary files.

• temp (System Temp): This folder (usually C:\Windows\Temp) is where Windows and system-level services store their temporary files.

• prefetch: This folder (C:\Windows\Prefetch) contains small files that help Windows open your frequently used applications more quickly.

Method 1: The Easy Way Using Disk Cleanup

For most users, the built-in Windows Disk Cleanup utility is the safest and easiest way to clear out temporary files.

1. Press the Windows key + R to open the "Run" dialog box.

2. Type cleanmgr and press Enter.

3. If prompted, select the drive where your operating system is installed (usually C:) and click OK.

4. Disk Cleanup will scan your computer. Once it's done, click the "Clean up system files" button. This will restart the scan with more advanced options (you may need to select your C: drive again).

5. After the second scan, scroll through the "Files to delete" list.

6. Check the boxes for:

   • Temporary files

   • Temporary Internet Files

   • Delivery Optimization Files

   • Thumbnails (optional, they will be recreated as needed)

   • Any other large "temporary" categories you see.

7. Click OK and then "Delete Files" to confirm. The utility will safely remove the selected files.

Method 2: The Manual Way (For Power Users)

If you're more comfortable with Windows or Disk Cleanup didn't clear everything, you can delete the files manually. It's a good idea to close all your open applications before you begin.

Step 1: Clear User Temp (%temp%)

1. Press Windows key + R to open the "Run" dialog.

2. Type %temp% and press Enter. This will open your user's Temp folder.

3. Press Ctrl + A to select all files and folders.

4. Press the Delete key (or Shift + Delete for permanent deletion).

5. You will almost certainly see a "File In Use" prompt for some files. This is normal. Check the box that says "Do this for all current items" and click Skip.

Step 2: Clear System Temp (temp)

1. Press Windows key + R again.

2. Type temp and press Enter.

3. You may see a permission prompt to access this folder. Click "Continue".

4. Just like before, press Ctrl + A to select everything, press Delete, and Skip any files that are in use.

Step 3: Clear Prefetch

1. Press Windows key + R one more time.

2. Type prefetch and press Enter.

3. Click "Continue" at the permission prompt.

4. Press Ctrl + A to select all files, press Delete, and Skip any files that cannot be deleted.

Is This Safe? A Quick Note.

Yes, deleting temporary and prefetch files is safe and will not damage your computer or delete your personal data.

• "File in Use" is Normal: You can't delete temporary files that are actively being used by Windows or a running program. This is why we click "Skip".

• Program Launches: After clearing the prefetch folder, the very next time you open your common programs, they might start a tiny bit slower. This is because Windows has to recreate the prefetch file for that application. This only happens once, and it's a very minor effect.

It's a good habit to clear these files every few months to keep your system tidy and your disk space free.