Applies to- QuarkXPress 2019 ,QuarkXPress 2018.QuarkXPress 2017

Summary:QuarkXPress doesn’t allow any 2 resources like style sheets, colors, etc. to have the same name. The crash while appending stylesheets from the document might occur due to the presence of style sheets having same name. 

Solution :

  1. Launch QuarkXPress and open the project.
  2. Open Style sheet palette and check if you find two or more stylesheets having same name.
  3. Rename the style sheets having same name and save the project.
  4. Now, append all the style sheets in any other project.