My mac air is shutting down right after I sign on.
You might try starting up in Safe Mode then removing login items and seeing if that helps.
And how do I remove login items.....?
System Preferences, Users & Groups, Login Items
I assume by "sign on" you mean "log in" ?
If it is dying earlier than that, but you can start in Safe Mode, you probably have some third party software conflict.
Yep...seems to have done it! New Itunes was sitting in login! Muchos gracias!
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