Find "Access Point Names"
Press the menu icon.
Press Settings.
Press Mobile network.
Press Access Point Names.
Delete data connection
Press the required data connection.
Press Menu.
Press Delete APN.
Press the Home key to return to standby mode.
Find "Mail"
Press the menu icon.
Press Mail.
Select email account
Press the name of the email account.
Press the required email account.
Delete email account
Press Menu.
Press Settings.
Press Delete account.
Press OK to confirm.
Exit
Press the Home key to return to standby mode.