get rid of file extension association RRS feed

  • Question

  • In Windows 8, I accidentally associated dll files with notebook and need them to be associated with nothing - I've figured out how to change the association to another program but cannot figure out how to return them to unaffiliated status. The earlier posts are not applicable to Windows 8.
    Sunday, February 3, 2013 6:33 AM


  • Windows includes a command-line utility "ftype" and also "assoc" - these two utilities can be used to manage file-type associations.

    open a CMD console window (search for CMD), and run-as-admin.

    ftype /?


    assoc /?

    this will show you the built-in help and usage for these tools.

    as an example, on my Win7 pc, I don't seem to have anything defined as an "open command string" for dllfile, so perhaps what you need to do is to delete the incorrect "open command string" you have accidentally defined?

    e.g. from my system:

    C:\Users\anyuser>assoc .dll

    C:\Users\anyuser>ftype dllfile
    File type 'dllfile' not found or no open command associated with it.


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    • Proposed as answer by Arthur Xie Monday, February 4, 2013 6:11 AM
    • Marked as answer by Arthur Xie Wednesday, February 27, 2013 8:32 AM
    Sunday, February 3, 2013 8:03 AM