In a support bulletin, Apple on Monday acknowledged an issue specific to dual-band Wi-Fi routers — those that are compatible with both 2.4-GHz and 5-GHz spectrum bands.
“Under certain conditions, iPad may not automatically rejoin a known Wi-Fi network after restart or waking from sleep. This can occur with some third-party Wi-Fi routers that are dual-band capable when: Using the same network name for each network, [or] Using different security settings for each network,” Apple wrote.
Typically, dual-band routers transmit both the 2.4-GHz and 5-GHz bands as one network with the same name and password. Apple recommends splitting the bands into two separate networks, naming them differently and making sure that both networks use the same type of security (WEP, WPA, WPA2, etc).
If all else fails, Apple recommends resetting network settings in the iPad’s Settings app (Settings > General > Reset > Reset Network Settings).
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