Chosen Solution

I have a i7 7700k, Asus Z270E and 2 sticks of Corsair LPX 8GB DDR4 2400mhz. I cannot run them in any configuration other than slots B1,B2.

This sounds like a slot issue. Try taking the sticks out and blowing out the slots, then verifying you have the correct configuration your motherboard manual says. Beyond that, resetting your UEFI may help. Hope that helps!

This is my mobo: https://www.asus.com/Motherboards/Z87C/

This is my RAM: http://www.gskill.com/en/product/f3-2133…

Works fine in slot 1-2 (Single channel) and 3-4 (Single channel), but whenever I try 1-3 or 2-4 (Dual channel), my computer won’t start.

Both my RAM and mobo are capable of dual channel.