Common Error Codes and Causes

When receiving an error code from a Solid server, it might not always be immediately obvious what caused them. This page lists a number of error codes and common causes when encountering them in Solid apps.

401 Unauthorized

Indicates that the Resource to access is only accessible to certain agents, but the current user is not logged in.

If the user is logged in but still receives this error, you might not have passed the session’s fetch() function as an option to the function sending the request.

403 Forbidden

Indicates that the current user is logged in but does not have the required level of access to the resource.

404 Not Found

Indicates that the Resource the user is trying to fetch does not exist.

412 Precondition Failed

Indicates that a condition that is set by solid-client before proceeding with the request is not met.

For example, creating a new Resource, such as with saveSolidDatasetAt, has the precondition that the Resource must not already exist. If the error is received for the create request, it indicates that the Resource already exists. To resolve, either:

  • Delete the existing Resource (e.g., using deleteSolidDataset) first and then recreate it, or

  • Fetch the existing SolidDataset using getSolidDataset) and applying changes to that.