Losing pc video signal through projector Pioneer VSX-820-K


Dec 24, 2014
Best regard
Currently I have connected my DVD player, my cable box and my PC to a receiver Pioneer VSX-820-K with access to a flat screen TV, all with HDMI cables
Everything works perfect and I have video and audio on my TV every time I select that the device I want to see.
The problem now and the reason of this query is: I have purchased a projector Optoma GT760 to use as my screen and see everything; Like I do with my TV.
when I use my receiver as a source I get all signals (DVD, cable box) except my PC, the message on the projector is "found signal but unknown" but still does not show any kind of image.
I already did the exercise connecting directly my PC to the projector and works perfect; the projector recognizes my PC..
I've tried changing my PC at different inputs of the receiver and the screen resolution on PC and the result is the same, no PC video.
In summary:

DVD, Cable Box, PC + HDMI + Receiver + HDMI + TV = OK

DVD, Cable Box, PC + HDMI + Receiver + HDMI + Projector = PC signal lost.

What I'm doing wrong?
What I'm don't doing yet?
Any suggestion I'll be pleasantly grateful.