Extrude Error

[gtprototype]

Extrusion error after edit.  Unable to resolve lost profile.  Cannot select closed profile to extrude.  

Simplified file attached.

[KristianLaholm · Accepted solution]

Edit Sketch3, and in the Sketch palette check the "Show Profile" box.
Edit Extrude feature and select profile.
Looks to me that you have hidden the profiles by mistake.

[gtprototype]

@KristianLaholm, @jeff_strater 

Dang! I honestly didn't turn it off however, as soon as I read you solution I realized I've encountered this before although it wasn't exactly the same circumstance.  As always, I search the forums for a solution prior to posting although I wasn't able to find that post before I posted this time.  I looked back through my posted links and found it here: https://forums.autodesk.com/t5/fusion-360-support/unable-to-select-sketch-for-extrude/m-p/10282414#M... 

I don't fully understand what "show profile"  does since the profile is still visible, if it just makes it unselectable perhaps changing the appearance of the profile would be a good indication it's active; at the very least renaming it to "show profile area" or something would be a good idea.

Thank you very much for your help!!

[davebYYPCU]

Your query is about terminology, 

For some reason the profile was missing from the extrude, 

sketch 3 has had the profile toggled off.  That then removes the profile from the extrude, and it goes yellow.

When you say but the profile is still visible, not really, the sketch articles that form the profile boundary are visible but the blue shading (profile) is off.  Extrude needs the blue shading, not the outline.  (Unless you are in Surface mode.)

Easy fix, as outlined above, 

Might help....