Thanks for joining this thread, @Patrick Kolasinski.

I appreciate the steps you've done to get this working. Allow me to chime in for a moment and share some additional information about printing invoice in QuickBooks Desktop (QBDT).

At this time, we're unable to suggest any Application programming interface (API). Just to confirm, is your QBDT still crashing even after performing those troubleshooting steps? If so, instead of printing them all at once, try to print at least 100 invoices first to double-check.

If the issue persists, try running the PDF and Print Repair Tool. This will help fix printing issues, including QuickBooks not responding and Unrecoverable errors. Here's how:

1. Download and run the PDF and Print Repair Tool.
2. Once the tool completes, try the .pdf file-related task that originally generated the error.

For your reference, you can also check out this article for further guidance: Troubleshoot PDF and Print problems with QuickBooks Desktop.

That should get you fixed right up. Please let me know how it goes so I can get back to you right away. I'm always here if you have any follow-up questions or concerns. Wishing you all the best!