Tax Code was not found in your company. Please, create it in QuickBooks Online and Sync this transaction again.

Hello usereprovencher, 

Welcome to the Community! QuickBooks Online allows you to set up federal and provincial tax codes in a few easy steps. I'd be happy to walk you through this process. 

It sounds like the issue with tax codes arises while trying to sync QuickBooks Online to a 3rd party application. Sales tax codes are required in order to sync transactions into the program. If you haven't set this up in your company yet, don't worry it's a quick process. Here are the steps to do so: 

• From the left menu, select Taxes.
• Select Sales Tax. 
• Towards the top right, click Manage sales tax.
• Select the Add tax button.

From there, choose the appropriate tax type and finish filling in the required information. You can find more details about the different tax types and how to use them in this article: How to set up a new sales tax code

If you've already set up the sales tax code correctly, then this may be an issue with your internet browser. A buildup of tracking cookies and cached files over time can cause performance issues for online programs such as QuickBooks Online. Please give the following steps a try, checking back between each to see if you can successfully sync with the app you're trying to use: 

• Clear your browser cache if you're using a browser
• Clear the app cache if you're using the QuickBooks Online app for Windows or Mac
• Try a browser if you're using the app
• Try a private browser window
• Try another browser type
• Make sure you're using a supported browser and system
• Reset your Internet or try on another computer or device

If you continue to receive the message after trying these steps, you may want to reach out to the 3rd party app's support team. You can find the support contact information for a given app by going to the Apps menu, then My Apps to view the apps you currently have connected. Clicking on the app that you're trying to sync will bring up a window that has the contact info on the right-hand side. You may need to scroll down to view it depending on the length of the app description. 

Please reach out if you're still experiencing this issue. I'm here to help!