Error Code 6000 typically points to a system issue or a data-related problem within your account, Heinrich.
In the meantime, you can delete the cache files of your default browser to remove outdated and damaged data that may cause unnecessary errors. Browser cache and cookies can interfere with the functionality of QBO, especially after an update. Alternatively, you can use other supported browsers to get around with this.
If you need to make changes or update your sales tax rate to ensure you collect the correct amount, you can refer to this article: Edit sales tax rate.
If you have any further questions or need additional assistance with QuickBooks, please feel free to leave a comment below. We’re here to provide prompt assistance.
