I understand the hassle that this caused you, QuickieSuxx. 

I'm here to shares some details about the error that you've encountered in QuickBooks Online.

First, you can manually remove the taxes on the transactions. All you have to do is deselect the TAX column. Then, Save and close.

If the issue still persists, you can perform some basic trouble shooting steps. 

To check if the browser is already full of frequently accessed page resources, causing some unusual responses, try signing into your QBSE using a private browser (incognito).

Here's how:

• Press Ctrl + Shift + N (Google Chrome)
• Ctrl + Shift + P (Firefox)
• Control + Option + P (Safari)

If it works, return to your default browser and perform a clear cache to refresh the system. However, if the issue persists, try using other supported browsers.

As mentioned by my colleague above, after you activated the automatic sales tax, you're unable to turn it off in QuickBooks Online. Though, you can edit the customer's tax information to ensure you will not collect any taxes.

I'll guide you how.

1. Go to the Sales tab and then select Customers.
2. Click the Edit tab.
3. Open the Tax info folder and select the Default tax code.
4. Click on Save.

The tax rate will no longer apply every time you create an invoice for this customer

Additionally, I've added an article that'll help you to file your sales tax return and record your tax payment in QuickBooks Online. To learn more about the process, please click here. 

Reach out to me if you have additional inquiries about Sales Tax or any QuickBooks related. I want to make sure you're taken care of.