421
421 Misdirected Request Error
What This Error Means
The 421 Misdirected Request error happens when a request is directed at a server that is not able to produce a response. This often occurs with HTTP/2 connection reuse where a single connection is used for multiple domains that resolve to the same IP but have different SSL certificates.
Common Causes
- HTTP/2 connection coalescing issues.
- SSL certificate mismatches on shared hosting.
- Misconfigured load balancers routing traffic to the wrong backend.
How to Fix It (For Users)
- 1 Clear your browser cache and cookies.
- 2 Try accessing the site in Incognito mode.
- 3 Use a different browser to force a new connection.
For Site Owners / Developers
- Disable HTTP/2 connection reuse if certificates do not match.
- Ensure your SSL certificates cover all domains served by the IP.
- Check load balancer configuration for correct host header routing.
When It Is NOT Your Fault
If the server's HTTP/2 implementation is aggressive with connection reuse.
Check if this outage affects everyone globally
This error often indicates a wider problem. Use our tool to verify if the site is down for everyone.
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