If someone is looking for the procedure to unlink a Gmail account from Yahoo then, they should sign into their mail account. Go to the Settings option from the bottom and then, move ahead with the Gmail account for removing/unlinking it by moving ahead with the section “Linked Account”.
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http://yahooukphonenumber.tumblr.com/post/661918081055113216/can-i-unlink-my-gmail-from-yahoo-mail