What does this mean?

WARNING: node without a volume node has 4 tiny portals

That error popped up after butting up a portal cell against a house prefab. It has coordinates, but I can't find the error.

Is there anything there that you can actually see? Did you try putting a brush around the coordinate and clicking the "include everything inside the brush" button on the menu? Its the 12th from the left next to the clipping button...

It might highlight the item...it might be really really tiny and hard to see....then you can delete it...

The error messages arent always very descriptive of your problems

Hope this helps...

Thanks Bloodletter. Yeah I tried that but nothing shows up. It's inside a prefab of one of the houses from Blackout. Even if I enter the prefab I still can't find it.

What's weird is, as I continue portaling a few more areas of the map, the error will either be there or it won't.

If the map compiles, plays and updates, then don't worry about the error. Sometimes this error causes the map not to update, and other times, it doesn't.

oh i hate those errors, one way i can tell u ( from experience ) that it is from a brush that u might have clipped and it looks normal but for some reason its giving u this error, just press E and make sure that ur brush's corners are on a grid point. thats how i got rid of my old errors.