Open system preferences > click on network ,if you are the administrator , enter your admin name & password to open the pad lock .
Keep the settings : location as Automatic , click on advanced > Wi - fi check the box of remember network this computer has joined , security as WPA2 personal AES , DNS settings as 8.8.8.8 and 8.8.4.4 , no proxies must be enabled , finally click on apply .
Regarding keychain , when you open safari & its preferences > click on auto fill , check all options so that when ever you login , your web mail , admin name passwords get automatically filled up in the keychain .
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