We are currently experiencing a critical issue with our website, and users are unable to access it. Could you please investigate and resolve this matter as soon as possible?
[Issue Details]
When attempting to access our URL, a Cloudflare error screen appears with the message "Error code 526: Invalid SSL certificate."
[Affected Site Information]
Domain / Hostname: nforum.ncatlab.org
Timestamp (UTC): 2026-06-05 23:22:24 UTC
[Error Status]
Error Code: 526Message: Invalid SSL certificateStatus Details: Browser (Working) / Cloudflare (Working) / Host (Error)[Requested Action]Since Error 526 indicates an issue with the origin server's SSL certificate (such as an expired certificate or a configuration mismatch with Cloudflare's Full (Strict) SSL mode), please check the SSL certificate status on our host server. If it has expired or is misconfigured, please renew or fix the settings.I have attached a screenshot of the error page for your reference.
Please let us know the cause of this issue.
Thanks,Ryo Takayama
We are currently experiencing a critical issue with our website, and users are unable to access it. Could you please investigate and resolve this matter as soon as possible?
[Issue Details]
When attempting to access our URL, a Cloudflare error screen appears with the message "Error code 526: Invalid SSL certificate."
[Affected Site Information]
Domain / Hostname: nforum.ncatlab.org
Timestamp (UTC): 2026-06-05 23:22:24 UTC
[Error Status]
Error Code: 526Message: Invalid SSL certificateStatus Details: Browser (Working) / Cloudflare (Working) / Host (Error)[Requested Action]Since Error 526 indicates an issue with the origin server's SSL certificate (such as an expired certificate or a configuration mismatch with Cloudflare's Full (Strict) SSL mode), please check the SSL certificate status on our host server. If it has expired or is misconfigured, please renew or fix the settings.I have attached a screenshot of the error page for your reference.
Please let us know the cause of this issue.
Thanks,Ryo Takayama