I had posted this problem before about adaptive geometry. I was shown to go into the document settings tab and then modeling and uncheck the box for adaptively used in assembly. Then I was able to project geometry to a part from some where else. I updated to 2014 and now it does not work. I also tried holding down the shift key and it still gives me the famous message and will not allow me to projec the geometry. This is killing me.
Stop using projected adaptive sketches? Please don't take that the wrong way (OK, it's poorly worded) but there are many reasons you should consider alternative workflows that don't kill the performance of your models - and are far more reliable and future-proof. Just because you can create adaptive-cross-part projected-geometry doesn't mean you should.
Check out http://forums.autodesk.com/t5/Autodesk-Inventor/Cannot-make-part-adaptive/m-p/3612870#M447425
(I think this might be very similar to your post)
And then this one for all the reasons you should stop and have a think about the processes you are using: http://forums.autodesk.com/t5/Autodesk-Inventor/Adaptivity-Woes-with-bizzare-solution/m-p/4339211#M4...
Peter