Hello there, MJPR2018.

I've checked our system and the investigation is already resolved. The error is caused by an older release of Microsoft Office. We recommend you update to the latest release to resolve this issue. If you have windows, you can open an MS Word document and click File from the menu. Click Account or Help and you'll see the Office version, then select Update. 

After updating Office, open your QuickBooks Desktop Company update it to its latest release. Then, try sending an invoice again. 

If you still get the same error, you can follow the steps provided by my colleague on how to contact us. This way, we can open a new investigation. 

Keep me posted on how this works. I'll be around the corner to assist you. Take care!