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An item with the same key has already been added. Key: Mono.Cecill.dll

Discussion in 'Editor & General Support' started by davenirline, Apr 17, 2019.

  1. davenirline

    davenirline

    Joined:
    Jul 7, 2010
    Posts:
    945
    Upon upgrading to Unity 2019, I got so many missing reference errors. I use assembly definition files so I thought the problem might be there. However, when I click on one, this message shows on the inspector:

    upload_2019-4-17_14-40-48.png

    I opened the assembly definition file on a text editor. There were no changes to them. How can I fix this?
     
    davenirline, Apr 17, 2019
    #1
    sxnorthrop likes this.

  2. sxnorthrop

    sxnorthrop

    Joined:
    Sep 29, 2014
    Posts:
    43
    Yep, currently getting the same error:
    upload_2019-5-30_10-57-25.png

    I cannot use my project at all.
     

    Attached Files:

    sxnorthrop, May 30, 2019
    #2

  3. jwittner

    jwittner

    Joined:
    Dec 2, 2015
    Posts:
    6
    I'm seeing the same thing in a project I'm working on. Have either of you found a work around?
     
    jwittner, Aug 28, 2020
    #3