“Can’t establish a reliable data connection to the server” syncing Android phone with Google account

My wife was trying to sync her data from her old Android phone to a Google account so she could transfer them to a new Android phone. Whilst trying to add her Google account to her old phone, she kept getting this error message:

Can’t establish a reliable data connection to the server. This could be a temporary problem or your SIM card may not be provisioned for data services. If it continues, call Customer Care.

Annoying, huh? Search the internet and you get forum thread after forum thread of people having the same problem over years. Many people seemed to suggest that the only solution was to do a hard factory reset, losing all of your data in the process which totally defeated the object!

Hilarious, then, to discover this super simple solution:

“Just try signing into the YouTube app with the account you want to sync and it will automatically add it to the list of your accounts. Kapish!”

Sure enough, that instantly fixed the problem in a matter of seconds. Amazing!