To start the Duplicate File tool, open CCleaner and go to Tools, and then select the Duplicate Finder. This presents a list of options, allowing you to match files by:
- Date Modified
- Content (this also implies and thus requires the Size criteria to be checked)
Please note that all of the selected criteria must apply to files for them to be considered duplicates - for instance, if both Name and Size selected, two files must be detected that have precisely the same file name and precisely the same size before the Duplicate File Finder will list these as possible duplicates.
You can select which files to ignore using the checkboxes in the ‘Ignore’ section of the page. Similarly, files must match none of the selected ignore rules in order to be listed as duplicates. For example, if a file is marked as hidden in the computer’s file system and the Hidden Files ignore rule is selected, it will not be considered a duplicate even if it would otherwise be because of the other criteria.
You can then specify extra drives and/or folders to include or exclude using the Include and Exclude tabs. To start the finder, click Search.
Note: If an Include Rule is set to Include files only, it will only Include the specific folder selected. Please select Include files and subfolders to have it check subfolders as well.
You can delete files by ticking the checkbox and selecting Delete Selected. Please note it is not safe to remove all the duplicates CCleaner finds.
Which duplicates should I delete?
The Duplicate Finder can search for files with the same File Name, Size, Modified Date and Content; however it isn’t able to determine which files are needed and which can be safely deleted.
For this reason, after searching for duplicate files, we recommend that you review the file path and, if necessary, the file itself to ensure that it is in fact a duplicate and not needed by a program on your computer. You can open a file from the Duplicate Finder screen by right clicking the file > Open Containing Folder, then double clicking the file in the window that opens.
We would also recommend that you do not delete any duplicates that are located in C:\Windows or C:\Program Files, as it is likely that these files will be required for a program to run.
It is normally safe to delete duplicates of your personal pictures or films, but as before, ensure that you verify the file path and the content of the files before deletion.
If you have determined that, for instance, every duplicate file detected by the search in your Pictures library (C:\Users\[user name]\Pictures by default), you may right-click on a file in that folder > Select Duplicates In > select the folder. This will check the check-boxes for all detected duplicates in that location.
Additional selection options can be found by right-clicking on files, such as excluding duplicates in a location; restricting the list of results to a particular location; selecting all duplicates of a particular type in a duplicate group; and saving the list of detected duplicates to a text file for later perusal.