You can try a few troubleshooting steps to check if we can open the quarterly or W-2 forms.
You can open an Incognito window and do the task there. If it works, you can go back to the main browser and clear the cache. This way, the internet files that may be causing the cache issue will be deleted. Then, I recommend using different browsers like Google Chrome, Mozilla Firefox and Internet Explorer.
Please let me know if you can open the quarterly and W-2 forms.
Thanks for joining this thread. I'm here to guide you to the right support so you can get the help you need.
Have you tried to process the troubleshooting steps provided by @Joyce_P? If the issue persists, I encourage you to get in touch with our QuickBooks Online Support Team to investigate this further. They can also create a new investigation for this issue and once it has been open, you'll be receiving an email notification about the updates and progress.