unable_to_create_user

What is it?

This error occurs when Better Auth fails to create a new user during the authentication process.
It typically happens during OAuth or SSO-based signup flows when a new user record is expected to be created but the operation fails.

Common Causes

• Database write failure due to connection issues, timeouts, or transaction errors.
• Missing or invalid required fields in the user schema.
• Unique constraint violations (e.g., email already exists).
• Mismatch between your database schema and the expected Better Auth schema.
• Errors thrown inside custom database hooks (e.g., user.create).
• Misconfigured adapters or database clients.

How to resolve

Verify database connectivity

• Ensure your database is reachable and properly configured.
• Check for connection pool issues, timeouts, or failed queries.

Validate schema and constraints

• Make sure all required user fields are present and correctly typed.
• Check for unique constraints (e.g., email conflicts).

Run migrations

• Ensure your database schema is up to date with the current Better Auth version.

Review custom hooks

• If you are using databaseHooks.user.create, ensure it is not throwing errors or returning invalid data.

Inspect logs

• Check server logs for detailed error messages during user creation.