Safari can't open the page because the server can't be found.
iPad mini, 5th generation, iOS up-to-date. Intermittently receive the above message on certain websites. Eventually, it clears, but happens again unexpectedly.
iPad mini 5, iPadOS 17
Question marked as
You might have an issue with DNS failing to resolve server addresses. As diagnostic exercise, try changing your local DNS Settings from Automatic to Manual - and replace the automatically selected DNS servers with those of Quad9, OpenDNS or Cloudflare.
Settings > WiFi > [Your WiFi SSID] - tap the “i” icon - then Configure DNS > Manual - finally replace the listed DNS servers.
Here are the DNS Server addresses for Quad9:
9.9.9.9
149.112.112.112
2620:fe::9
2620:fe::fe
Enter all four IP Address (two are IPv4, two are IPv6) exactly as shown - one per line. The sequence of the server addresses is immaterial.