Net connection problems

[PW_VOX]

Yesterday i encountered the dreaded schematic and board out of synchronisation error.  I've posted about it elsewhere, but I think it was due to an internet connection problem.  I ran ERC and as well as identifying the problem it offered me a tool to fix it (thanks!) which I hadn't seen before.  After completing the fixes and saving, everything looked good except I had lost an hour or so work.  However, I subsequently noticed that quite a lot of parts had pins which has 'X' symbols over them instead of an airwire and I could not start laying out track from them.  I saved the board and came back to it this morning.   The X symbols are now gone but there are still no airwires.  For example, pin 5 in this snapshot.

and I still can't start routing from them.  Note that the net name on the pin is correct.  However, if I bring a part that is connected to that net close to the pin the airwire is restored between the components like this.

What's going on? Is there any way to restore the all the airwires? 

[jorge_garcia]

Hi @PW_VOX,

I hope you're doing well. There are a couple of things that could be going on here. First, keep in mind that airwires always look for the shortest distance if you want to route two pads in a different way just route towards the pad you want to route to and eventually the airwire will jump. Second run ERC again just to confirm everything is still in sync. Next, check your schematic, is everything drawn on a 0.1" grid or metric equivalent? If the schematic wasn't drawn to this grid setting it's possible the connection you are looking at is not properly formed. You can confirm this by moving the component in the schematic if the nets follow it and stay connected then the connection was properly formed. Finally make sure that the airwire has not been consumed by a polygon. Once a polygon fills and connects to a pad the airwire goes away.

Let me know if there's anything else I can do for you.

Best Regards,