Please refer to the steps below.
1. Log in an account with Administrator rights.
2. Close all programs that are running.
3. Click Start -> Programs -> Accessories -> System Tools.
4. Click Disk Defragmenter.
5. Select the drive to defrag and click Defragment.
6. Click Close when defragmentation is complete.
7. Click Close to close the Disk Defragmenter window.