When I try to set up my sales tax, I'm getting this error: An application error has occurred while processing your request Any idea on how to fix it?

I am receiving this error also.

Thanks for posting here and sharing this concern with us, @hulljohnd and @tlp97,

I want to make sure this is resolved immediately for you. While there is currently no reported issues or open investigations for the sales tax preference in QuickBooks, let's try to diagnose this issue by running some basic troubleshooting on your computer.

First, use a different browser and try to set up the Sales Tax preference and see if works.

If not, you can use a private window and login to your QuickBooks account in there. Unexpected issues in QBO are most of the times affected by the large data in the cache. This is because the regular browser will constantly accumulate data and will not remove its history automatically.

The incognito mode will not save any history, so it's a great place to identify issues in the browser. Use these keyboard shortcuts to launch a new private window:

• Google Chrome: press Ctrl + Shift + N  
• Mozilla Firefox: press Ctrl + Shift + P
• Safari: press Command + Shift + N

If it works, clear the cache to resolve the issue in regular browsing.

Please update me with the result after trying the troubleshooting steps. I want to make sure this application error resolved. I'll also be right here if you need further assistance.