The 767s autoland crosswind capability is 25kts, except on a contaminated runway, where it is 12kts, or very low visibility (<1200m/<600m) where it is lower (15kts/10kts respectively).
The autopilot will still attempt the autoland if wind speeds exceed these limits, but Mr. Boeing cannot guarantee that it will be successful. Once the runway alignment process takes place the autopilot will go to the limits of yaw and roll to try maintain localiser, if the wind is stronger than it allows for then the aircraft will fly out of tolerance and a go-around would have to be initiated. The same applies on the runway, however a wet runway could allow the aircraft to slide off the side, thus the lower limit.
The go-around is initiated if below Cat 1 minima and the aircraft is outside tolerance, normally autocoupled. If at or above Cat 1 minima and the crew becomes visual the autopilot may be disengaged and the approach flown manually. This is known as reversion and allows up to 33kts (+5kt gusts) of crosswind.
Depending on the airline's procedures use of the go around switch is required for a missed approach to apply thrust to GA limits and provide pitch and roll guidance to the flight directors. Not activating the TOGA switches was cited as one of the causes for the QF1 accident at Bangkok:
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Photo © K W Chuihttp://www.atsb.gov.au/aviation/acci/ojh/index.cfm
Whether or not the autopilot is engaged is another matter. The MA can be flown manually, but as it is a relatively high workload period the AP relieves some pressure!
Hope this helps.