The icon will appear as a set of grey gears located on your Home Screen.;
, It is located in the fifth set of menu options.
 It is located in the fifth group of menu options.
 The email domain is the part of an address that comes after the @ symbol, such as “@gmail.com,” “@yahoo.com,” and “@outlook.com.” When writing an email, any email address that doesn’t have this domain will appear red in the “To” and “From” boxes. This will let you know if you are using or writing to an email address that doesn’t have this domain.
Open your iPhone’s Settings.
Scroll down and tap Mail.
Scroll down and tap Mark Addresses.
Input your email domain.
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