There are no files to download and update, everything required for extended functionality already exists in the main application. If the plug-in is not registered, it works in DEMO mode. This means you can do everything but you will not be able to import more then 5 items at once. To unlock its functionality, you have to purchase a license and register this extension.
Registration requires a license key. Seethis article regarding registration issues. You can reset addon's license (due to hardware change etc.) in the same way as the main software license.
The instruction represented below is identical regardless what Store Manager you have. The illustrations below were provided from the Store Manager for Prestashop as an example.
QuickBooks Integration registration:
After purchase, all customers receive an email notification with registration information. You may find License Number (Regcode) there.
Open "Preferences" and activate the "Addons" tab to see the list of available addons. The addon is unregistered now.
Possible registration statuses:
Unregistered - extension is working in DEMO mode
Registered - addon is registered and fully functional
Verifying... - software is checking registration information
3. Click the registration status, QuickBooks Integration registration window will appear. Enter your license key in the relevant field and click the [OK] button:
Store Manager will check the license code and return the status.
If activation is successful, you will see green color text "Registered."
Now QuickBooks Integration addon is registered.