Sorry for the language because I'm French. So how can I solve this message?
What type of files were/are they?
It could be because the files are protected or need admin permission to delete, for example system files.
Many system files do <em>need</em> duplicates and you should normally set the duplicate finder to ignore system files:
If they were your own files then it's more likely that they could not be deleted because they were open.
That will happen if you had opened the files to check which duplicate to keep and which not, and hadn't closed them again.
Hi nukecad, thank you for your answer but I have already ignored the system files.
I note that those are Avast files; are they connected with Avast Antivirus?
It could well be that Avast AV itself is protecting them from deletion.
As they and are not your own files (documents, photos, music, etc) and they are connected with software (they are in C:\Program Files\...) then it's usually best to leave them alone.
Ok and is there a way to ignore the Avast files? There is also a Microsoft Edge file that doesn't delete.
You can set exclusions in Duplicate Finder - but it's probably easier just to ignore them if they are not your own files.
See the NOTE below.
If you right-click on one of the files found then a context menu will pop up where you will be given a choice to 'Exclude >'
If you hover over that then you can add an exclusion for the directory, right down from C: to the directory containing the actual duplicate.
Usually you'll want to exclude just the directory containg the duplicate file, that directory will then be ignored in future searches.
Here is an example:
I set a search on filename only for "<em>C:\Programme files\*.*</em>" and it found 3 instances of '<em>uninst.exe</em>' for different CCleaner products - CCleaner, Defraggler, & Speccy.
I right-clicked on the one for 'Defraggler' and made the Defraggler directory an exclusion.
I then went back and ran the search again; as you can see here this time the uninstaller for Defraggler was ignored:
NOTE that there is no easy way to undo such an exclusion in the Duplicate Finder, once an exclusion has been set for Duplicate Finder it remains in force.
The only way I have found to remove such a DF exclusion is to delete the settings file "C:\program Files\CCleaner\ccleaner.ini", (or manually edit it if you undertand the ini file syntax).
Deleting 'ccleaner.ini' will reset CCleaner to it's default settings, so you'll then have to set all your ticks/unticks for Custom Clean and all your other custom settings up again.
Like i say - it's probably easier just to ignore the duplicate results if they are not your own files.