Can't Place Buried Vias in Multi-layer board

[jpicard]

I'm new to circuit design, and I"m trying to design a small board that has a large number of vias. It has 6 layer pairs and a copper top and bottom, and I've altered the via size to manufacturer's specs. Every time I place a via, and attempt to select from "Inner Layer 1", it says that it is now allowed. When I attempt to allow it by going to the PCB Properties window, there are no allowed vias that go from Inner Layer 1 to anything else, even though I have the boxes checked to allow blind and buried vias.

Thanks in advance, and let me know if I can clarify anything!

[Branch_Support-NIC]

Hi,

Under Options>>PCB Properties>>Copper Layers, there are checkboxes for blind and buried vias so if you’re planning to use these type of vias, make sure you check these boxes, otherwise, Ultiboard will place only through vias. Once you check the boxes, under Allowed vias there are various valid vias that you can place; make sure you check them as well.

A layer pair has two sides, so if you set the layers pairs to 6 it means you have a total of 12 layers. Copper top and inner 1 is the same pair, inner 2 and 3, 4 and 5..., inner 10 and copper bottom is the last pair. If place a blind via from copper top to inner 1, this is a valid via but if you placed a buried via from inner 2 to inner 3 this via setup can not be manufacturer and this is why you get a invalid via message from Ultiboard.