[▲ Vercel Community](/) · [Categories](/categories) · [Latest](/latest) · [Top](/top) · [Live](/live) [Help](/c/help/9) # The required http-01 challenge failed 18 views · 0 likes · 2 posts HGuaymas (@hguaymas) · 2026-01-09 My subdomain works with http but not with https. I’m getting the following error message:  system (@system) · 2026-01-09 The domain troubleshooting guide can help with most custom domain configuration issues. You might be able to use that guide to solve it before a human is available to help you. Then you can come back here and share the answer for [bonus points](https://community.vercel.com/t/introducing-the-vercel-leaderboard/1358). https://vercel.com/docs/projects/domains/troubleshooting You can also use [v0](https://v0.dev/) to narrow down the possibilities.
