Signals ChemDraw: "Failed to Initialize" error when saving on Signals ChemDraw for Mac

Updated: September 1, 2026

Details:

When trying to save a new document or use the Save As option in ChemDraw 26.0 for Mac, you receive a "Failed to initialize" error message:

Failed to Initialize window.external[n] is not a function (In 'window.external[n](e)', 'window.external[n]' is undefined)

Solution:

Our developers are aware of this behavior, which seems to have happened after a recent update from Apple.  A fix is expected to be released in the following weeks.

Workaround:

1. Open ChemDraw+ on your tenant URL
2. Create a new document there and save it.
3. Once you have it saved on the tenant, you can select "Download CDXML" to save it on your computer
   
   
4. Make a copy of the file and keep the original as a template.  You can then open the file in ChemDraw Desktop and make the changes to it.  You can rename the file before of after making the changes directly from the operating system.
5. Once a new file is stored in your computer, you can edit it and save the changes without any errors.