Why is the error Automation Error coming up in QuickBooks Desktop?

Overview

QuickBooks was opened and the error: Automation Error came up. It will not allow me to access the AvaTax configuration or open anything AvaTax related.

Environment

QuickBooks

Resolution

First try the following steps:
- In your File menu select Edit > Preferences and ensure that "Keep QuickBooks running for quick start-ups" is unchecked
  - If it is checked, uncheck this option and save your change
- Go to Edit > Preferences > Integrated Applications > Company Preferences
  - Make sure there is only 1 AvaTax listed
  - If there is more than one AvaTax application listed, please log into Quickbooks as the Admin user in Single-User Mode and delete the AvaTax application that does not match your current version of AvaTax
    - Found by going to File > AvaTax > Configuration > General Tab > Test Connection button
- Close the Quickbooks Application
  - Open up the task manager by pressing the CTRL+ALT+DEL keys or by pressing CTRL+Shift+Esc
  - In the Processes Tab of the Task Manager, right click on any item in the list which begins with QB, Quickbooks, Intuit, AvalaraEventCallback, or AXLBridge and select "End Process"
- Pull up a Windows Explorer and go to C:\Program Files or C:\Program Files (x86) and right-click on the Avalara folder
  - Choose Properties > Security > Edit
  - Make sure all "Group or User Names:" entries have Full Control
  - You may need to reach out to your Network Admin or IT department to have these changes made
- Reopen Quickbooks and go to File Menu > Avatax > Configuration
  - On the General tab, press the Test Connection button.
  - If the test connection is successful, try calculating tax
If the steps above do not resolve the issue, please try uninstalling and reinstalling AvaTax
- Either reinstall your current version or upgrade to the latest build available
- Make sure to take note of the license key and account number

Note: All machines with Avalara AvaTax for QuickBooks at your company must use the same version of our software. If you upgrade to a newer version of Avalara software on your machine, also upgrade the other machines at your company where Avalara is installed.