Windows 10: Unused File Extension Solved

  1. Posts : 56
    Microsoft Windows 10 Home 64-bit
       17 Nov 2017 #1

    Unused File Extension

    Once in a while I run CCleaner.
    When running Registry cleaner I encounter several "Unused File Extensions" entries.
    What app create these entries and why?
    thanks for any answer.
      My ComputerSystem Spec

  2.    17 Nov 2017 #2

    These are file extensions that are no longer used, as they may have been associated with removed Malware, or other programs that have been uninstalled, deleted or no longer used.
    However, we do not suggest using CCleaner's Registry Cleaner, or any other Registry Cleaner or Optimizer software for that matter. These usually cause more problems then they fix. Many of the threads on here start with "I ran this Registry Cleaner and now my computer won't...."
      My ComputerSystem Spec

  3. Cliff S's Avatar
    Posts : 21,739
    Win10 Pro, Win10 Pro N, Win10 Home, Win10 Pro Insider Fast Ring, Windows 8.1 Pro, Ubuntu
       17 Nov 2017 #3

    Sometimes they are just text files that have the same name, but the extensions(letters assigned after the period/point) are different, so a program can call up the subroutine.


    Routine dothis
    call up
    if =0
    then call
    if dothis =1
    then call
    and so on

    You can see this when looking at an installed 3rd party program and copying the file to the desktop and changing the extension to .txt.

    Here is an example of a .dll I change to .txt it's not readable though with out another program like Resource Hacker.
    Click image for larger version. 

Name:	image.png 
Views:	2 
Size:	203.9 KB 
ID:	164287
      My ComputersSystem Spec

  4. Posts : 56
    Microsoft Windows 10 Home 64-bit
    Thread Starter
       17 Nov 2017 #4

    thanks for your answer and for the advice re registry cleaners in general.
    much appreciated.
      My ComputerSystem Spec

  5.    17 Nov 2017 #5

    Just to add to the chorus: Never, ever, use any program that claims to "clean" your registry. They always cause more harm than good. There is no need to "clean" the registry.
      My ComputerSystem Spec


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