Hello cpapale-corflex-,
Welcome to Community! It's essential that you're able to view and print .pdf files in QuickBooks Online. I would be happy to help!
Initially, I suggest clearing the cache on your browser. An excessive amount of frequently accessed page resources can cause unusual behavior. In addition, you can try another browser such as Google Chrome, Safari, Edge, Firefox, or a private browser. If the issue persists, I recommend Updating, repairing, or re-installing your Adobe Reader.
Should you require additional assistance, please contact us outside of this forum. It would be our pleasure to work with you in real time, and ensure you're able to accomplish your QuickBooks goals without delay!
Feel free to reach out with other questions. We would be glad to assist!