[Answered] Why Does MP4 Make Duplicate Files in My Folder?

Why does MP4 make duplicate files in my folder?

Have you ever opened a folder and found multiple copies of the same MP4 file? This can be confusing and takes up valuable storage space. MP4 duplicates usually happen because of syncing errors, download problems, or issues with media players. The good news is that once you know the cause, you can take steps to fix and prevent it. Below is a table of common reasons why MP4 files might get duplicated in your folder:

Cause	Description
Cloud Sync Conflicts	Services like Google Drive or Dropbox may create duplicates during syncing, especially across devices or after network issues.
Multiple Downloads	Downloading the same MP4 more than once, especially if your browser doesn’t warn you, can lead to duplicates.
Backup Software	Backup tools may save extra copies if they detect minor changes, even if the file content is the same.
Incorrect Copying Process	Copying files between USBs or drives can create duplicates if the process fails or is repeated.
Media Player Glitches	Some players save extra versions or create temporary files that look like duplicates.
Malware or Viruses	In rare cases, viruses may duplicate files on purpose as part of their activity.

These problems usually happen in the background, so you might not notice them right away. But once you know what causes them, it’s easier to fix and avoid them. Now that you understand why MP4 files get duplicated, let’s look at how to find and remove them in Windows. This will help you clean up your folders and free up space.

How to fix MP4 files duplicating?

You can use 2 methods to find and clean up duplicate files like MP4 or other data. Below are the specific steps.

Fix 1. Scan and delete duplicate MP4 files with a handy tool

Using the built-in tools in Windows to find and delete duplicate MP4 video files can be slow and frustrating. A much easier and more effective option is to use a third-party tool like AOMEI Partition Assistant for Cleanup.

This powerful program is designed to help manage your hard drive and improve your computer’s performance. One of its handy features is "Duplicate File Finder," which can quickly scan any folder or drive you choose and safely remove extra copies of your video files. It’s user-friendly, whether you're just cleaning up your PC or handling larger tasks as an IT expert.

The software also gives you control over how the scan works. You can set it to search for certain file types, such as videos, pictures, music, or documents. If you ever remove something by mistake, You can use AOMEI Partition Assistant's "Recover Data" feature can help you easily find the deleted files.

Step 1. Install and launch AOMEI Partition Assistant for Cleanup. Click the "Find Duplicate Files" tab. You can either click "Scan Now" to start the scan of your system C: drive. Or, click "Custom Scan" to manually select paths to be scanned. (Here, we take the "Custom Scan" as an example.)

 

Step 2. After clicking "Custom Scan", all local and external drives on your PC will be displayed. You can also click the "Add Path" button, and then a browse folder window will pop up. So you can add more paths on this PC, like Desktop, Downloads, and other folder paths.

Step 3. Once necessary paths are added, you can click the "Scan Now" button to start the scan process.

Step 4. The scan process might take time. After the scan is complete, all duplicate files will be listed. You can click the button behind to locate them.

Step 5. You can either manually select duplicate files, or click the "Smart Select" button to automatically select unnecessary duplicate files to delete.

Tips: If the "Smart Select" is ticked, only the oldest duplicate file will be unticked. It means that all duplicate files except the oldest one will be ticked to delete. (The oldest file means the file that was created first. This file will not be deleted. All other duplicate files are conside red copies of the oldest file. )

If you manually select all copies of duplicate files, you will get a pop-up warning window to keep at least one copy of the duplicate files. If you indeed want to delete all copies of duplicate files, you can click "OK" so all copies of duplicate files will be selected to delete.  

After unnecessary duplicate files are selected, please click the "Clean Now" button to start the deletion.

Step 6. The deletion might take time. After the process is finished, the selected files will be deleted, and you will get a cleaning completed window displaying how much data you deleted in total. 

Fix 2. Manually find and remove duplicate MP4 files via Windows File Explorer

Windows File Explorer can also help  find or delete duplicate MP4 files, as it lacks any built-in feature to compare file content. While you can sort files by name, size, or date to try and spot duplicates, this process is completely manual and can be slow and inaccurate, especially if the files have different names but the same content. One advantage is that File Explorer is already part of Windows, so you don't need to install anything extra. However, the main drawback is that it doesn’t automatically detect or safely remove duplicates, which makes it hard to manage large numbers of video files efficiently.

Step 1. Press Windows + E on your keyboard to open File Explorer. Go to the directory or drive where you suspect duplicate MP4 files may be stored.

Step 2. In the top-right corner, you'll find a search bar. Type the following command and press Enter: ext:mp4 OR ext:mov OR ext:avi OR ext:mkv

This command tells Windows to search for video files with common extensions.

Step 3. After the search is complete, click on the "Size" column header to sort the files by size. This will help you identify duplicates that are often the same size.

Step 4. Carefully review the search results and select duplicate files by holding down Ctrl and clicking on each one. Once selected, right-click and choose "Delete" to remove them.

Windows File Explorer can be used to locate and delete duplicate video files, but the process is very slow and resource-intensive. You also can’t pause the task if you need to focus on other important activities, and it may be disrupted while you're using your computer.

Conclusion

Why does MP4 make duplicate files in my folder? There are many reasons. MP4 file duplicates can clutter your folders and waste storage, but they’re often caused by common issues like syncing errors or multiple downloads. By understanding these causes, you can take steps to avoid them. Whether you use a powerful tool like AOMEI Partition Assistant for Cleanup or manually search with File Explorer, cleaning up duplicate files can help improve your computer’s performance and free up valuable space.