Fix: Unable to Check for Update – iPhone
While searching for an iOS update on your iPhone (Settings -> General -> Software Update), you may receive the following message from Apple about not being able to find an update.
Unable to Check for Update
An error occurred while checking for a software update.
The error is related to the iOS software server not able to server your request. There may either be maintenance or downtime with the iOS software server at this time. Try your request again later. If the error persists, try connecting to a Wireless network or over your cellular connection.