Skip to main content
Avalara Help Center

How do I resolve 'Could not load type 'AvaTax.QuickBooks.Controls.ShowMesssage' in QuickBooks Desktop?


You are trying to access the AvaTax configuration no menu options open. You receive error

"Unhandled exception has occurred in a component in your application. If you click Continue, the application will ignore this error and attempt to continue.  

Could not load type 'AvaTax.QuickBooks.Controls.ShowMesssage' from assembly 'AvaTax.QuickBooks.Controls, Version=1.0.6239.19224, Culture=neutral, PublicKey Token=null'."



QuickBooks Desktop


  • This is a result of not running the AvaTax installer as an Admin (right click), not running QuickBooks as an Admin (right click on) and not choosing the QuickBooks Desktop - Application Certificate the first time.
  • Ensure Full Control is given to the Avalara folder (C:\Program Files (x86) for Users and the Trusted Installer
  • Uninstall and reinstall AvaTax for QuickBooks