# PCB design rule errors, but can't understand why

I am trying to create a PCB using NI Ultiboard. My circuit is a SECPIC DC-DC converter and controlling the L1 current. This is my circuit:

and I get this error:

Design rule error: Net "VOUT" close to net "3".
Design rule error: Net "3" close to net "VOUT".


This is the area of the error (zoom of the second picture):

I can't understand why I get this error, because in Multisim the circuit is working fine. Can anyone explain the cause for the error?