when start a new part, I select boss extrude, pick a plane, usually the sketch bar comes on but in sw 2015 it does not, why
I'm running SW2015 SP 2.0 and it is working fine. If you're seeing the sketch bar, what else are you getting?
I get nothing, the command manager is asleep, I have to select sketch
This is what I see when I follow your method, is this what you see also?
Your title is a bit vague.
when you start a new part, the features bar is highlighted, if you select extrude you pick a plane,the command manager automatically switches to sketch, in my sw 2015 it does not do this.
Like Deepak, it's still switching automatically for me, both with the workflow you described and with my usual method of selecting the plane first and then the Extrude command. I'm not aware of any setting that would cause it to stop.
check to make sure the "template" part (the part file that all users share from a shared location) isn't in mid-command. I've seen this quite a few times. Open your template part and you might find it in edit mode as well. As a last resort, delete your Template part file, and create a new one; just make sure you're settings are the same as the other users if you follow standards, and make sure you save the part file in ISO mode, before you press any command buttons.
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