hello, im very new to Mac OS as i've been using Windows eversince it came out. Recently i got a MBP 2013, it ran just fine without any problems, but after i did some changes in the system preferences, i noticed it required to enter the keychain password for several apps like talagent, safari,.. after booting up before i could use it. This morning i went through the aforementioned process again and upgraded my Mac from Maverick to Capitan, however now after booting up my MBP always freezes at the second step where it requires the Local Items keychain pw for Messages Agent. Tried to google and booted into safe mode but nothing changed. Any helps would be much appreciated! Thanks.