Error “Sorry, apps are turned off”: what to do

If you are trying to install the web part on a SharePoint 2019 server, you may encounter the following error when adding it to your site: "Sorry, apps are turned off. If you know who runs the server, tell them to enable apps."

Here are the possible reasons and solutions for this error:

Apps are not enabled in your farm	Ensure you have Apps enabled in your SharePoint 2019 farm.
Subscription service is not setup	The first and most likely problem is that the subscription service is not configured in your farm. Please configure it.
The app management service is not associated with your web application	Make sure the app management service application is associated with the web application where you want to add the SPFx web part.
App URL is not configured	If you have not configured the app URLs, please ensure you have given values to App Domain and App Prefix in your App Store settings.

If the error persists after following the above solutions, please create a ticket so our technical support team can analyze the problem.