500
500 errors in OpenPanel will display error ID.
openpanel error command can be used to display the error code for the id:
opencli error ID_HERE
403
403 errors are caused for one of the following reasons:
- user does not have the requested feature enabled
- domain is not owned by current user
- request is invalid
404
404 errors are caused for one of the following reasons:
- page does not exist / link is invalid
- module has been disbaled by Administrator
JSON
Most pages in OpenPanel and OpenAdmin support an optional ?output=json parameter. When added, the backend returns raw JSON data instead of rendering the usual template.
This feature is especially useful for developing custom code or plugins, as it allows you to retrieve data from other modules directly. It’s also helpful for troubleshooting, letting you determine whether an issue is template-related or originates from the backend.