Installed ChemDraw 19.x or 18.x and it crashes with an "unexpected" error as soon as you start it.
Remove any unwanted or unrecognized .plist files from the following folders:
If the issue continues after deleting the files, you can create a separate TEMP folder and put all the files in there as a backup. Then delete all the .plist files found in the original folders and try again.
If any other application gives you issues after doing this, you can go back and restore the file for that application to the original folder.
You can use the Go > Go to Folder option in Finder to go directly to the folders mentioned before in case you cannot see them through your Hard Drive icon.