Is It Safe to Delete Duplicate Files? A Detailed Guide

Duplicate files clutter up your hard drive and take up storage space, potentially causing your computer to slow down. Removing them can help improve file management and computer performance. However, is it safe to remove them?

In this article, I will discuss what types of duplicate files are safe to delete and show you how to delete them safely.

 Cisdem Duplicate Finder

Safe, Effective Duplicate File Finder

• Identify duplicate photos, videos, documents, audio files, and all other files
• Detect similar images
• Support Windows PC, Mac, external storage devices, cloud drives, and phones
• Scan for duplicate files in folders, iTunes, Apple's Music, and Mac's Photos
• Allow you to exclude important files and folders from scans to keep them untouched
• Let you conveniently view duplicates before deletion
• Automatically select all but one file for deletion in each set of duplicates, enabling you to remove all duplicates at once
• Allow you to adjust selections manually or choose from 8 rules (e.g., Select Newest)
• Offer 3 removal methods, including Move to Recycle Bin (PC) or Trash (Mac), making it easy to restore deleted duplicates when needed
• Easy to use and customize

Free Download Windows 10 or later Free Download macOS 10.11 or later GET IT ON Google Play Download on the App Store

Is it safe to delete duplicate files?

Now, let's dig a bit deeper.

What are duplicate files?

Strictly speaking, duplicate files are files that exactly identical (regardless of how they are named). If two files have the same format, size and name but different content, they are not a set of duplicates.

What duplicate files are safe to delete?

There are two types of duplicate files. Are both types safe to delete? Let's find out.

• System or app related duplicates: For a variety of reasons, your operating system itself may duplicate files in order to work properly. Duplicates can also be generated when you install or use apps on your computer. I call them system or app related duplicate files. You should not delete them. (If you are very tech-savvy and know exactly what you are doing, you may remove those you consider unnecessary if you really want to, but you still need to be cautious.)
• User-created duplicates: You may have created duplicates of your files unintentionally, for example, by importing the same photos multiple times, downloading a movie twice, or moving files using copy-and-paste. I call them user-created duplicate files. They are safe to remove if you are sure that you no longer need the duplicate copies.

Should you delete duplicate files?

Unnecessary duplicate files take up storage space and may make it hard to find you are looking for. If you are sure that they are truly duplicates and your computer or apps don't need them to work properly, it can be a good practice to delete them.

How to safely delete duplicate files

Knowing what duplicate files are safe to delete doesn't necessarily mean knowing how to safely delete them. Well, how do you perform a safe deletion then? Here are some general tips.

• Stay away from system and app folders, such as C:\Windows and C:\Program Files. What if you are not sure whether a folder is system or app related? If so, it's safer to just focus on your personal folders instead, such as Desktop, Downloads, and Documents.
• Optionally, back up your folder(s) before you remove duplicate files from there.
• Use duplicate file finder software instead of looking for duplicates manually. Software uses algorithms, which are far more reliable than the manual method.
• Configure a duplicate file finder correctly. Duplicate file finders may offer two methods for identifying duplicates: based on content or file names. Identifying duplicates by content is the most accurate.
• Move duplicate files to the Recycle Bin instead of deleting them permanently right away.

The following steps use Cisdem Duplicate Finder as an example to show you how to configure and use duplicate file finder software to achieve safe deduplication.

1. Download and install Cisdem Duplicate Finder. Open the app.

Free Download Windows 10 or later Free Download macOS 10.11 or later

2. Use drag-and-drop to add one or more folders where you think duplicate files exist to the app.

3. Optionally, click the Settings button in the top right corner to configure settings for enhanced security. Here are some examples.

• Ignore folders: Exclude the backup folder in Pictures from the scan for duplicates.
• Ignore extensions: Exclude system or app related files from the scan to add an extra layer or security if needed, such as dll, sys, ini, log, bat, and msi.
• Set deletion priority: If you are managing duplicate files between two folders and want to keep the files in one folder while removing their duplicates from the other, you can set a priority.

4. Click Scan.

5. When the scan is complete, the app will display all duplicate files in the results window, making it easy for you to view and examine your duplicates.

6. In each set of duplicates, the app automatically selects all but one file for deletion, making sure at least one copy of each file will be kept.

You can adjust selections to decide which copies to delete, either using manual adjustments or selection rules.

When you are happy with selections, click Delete, then confirm the deletion.

Now, all unwanted duplicates are moved to the Recycle Bin.

FAQs

Can deleting duplicates cause problems?

Deleting system or app related duplicate files can cause problems, such as causing your computer or a certain app to malfunction. Removing duplicates of personal files is usually okay if you are sure that you don't need them any more.

Is it safe to delete duplicate files found by CCleaner?

It depends on how you confiture CCleaner. Here's a safe way to configure it. Set it to identify duplicates by content and size, ignore system files, hidden files, and read only files, and only add your personal folders to scan. Not following these steps may lead to risks.

Also, it's important to take a look at the found duplicates. Since it doesn't provide a preview feature, you may need to open files in File Explorer to examine them.