Auth.js · browser URL
error=Configuration
/api/auth/error?error=ConfigurationWhat it means
This is a cover, not the real error. Auth.js only sends a few error types to the browser (AccessDenied, Verification, OAuthAccountNotLinked and a handful more). Everything else, like a missing secret or a database failure, shows up as Configuration so it can't leak details.
Common causes
- The real error is in your server logs, on a line starting with [auth][error]
- Most often MissingSecret, UntrustedHost or an AdapterError
How to fix it
- Open the logs where the app runs (Vercel → Deployments → Logs, or your terminal)
- Find the [auth][error] line and paste it into the box above
- Add debug: true to your NextAuth config temporarily if the line isn't there
Prompt for Cursor or Claude Code
Sign-in redirects to /api/auth/error?error=Configuration. Don't guess. Tell me where my server logs are for this host, then read the [auth][error] line and fix only that root cause.Not quite your error? Paste yours into the free VibeBoot Doctor or browse the Auth.js error fixer.
next: skip the next one
Skip the setup. The VibeBoot SaaS Starter ships Auth.js v5 already wired (GitHub sign-in, optional email magic links, Prisma adapter), plus Stripe and a database on Next.js 16.4.3. $49, one-time.
14-day money-back guarantee · lifetime updates
Other Auth.js errors
$ fixed it? get the next one first
New fixes for what AI agents break, by email.
When we add a fix or a Cursor rule for a new Next.js, Auth.js, Prisma or Stripe break, it goes out in the VibeBoot newsletter. Free, occasional, unsubscribe in one click.