Factorio Forums

Bug overview

This bug has 2 variants: either no underground belts are placed, or there are u. belts places but at wrong locations.
The bug happens only if having no underground belts in the inventory, if having a few of them, the placement works.

What did you do? What happened?

Place underground belts - see video.
Setup: drag begin -> empty tiles -> power pole -> belt running in a crossing direction -> empty tiles.

Result is either
- belts but no underground belts are placed
- unconnected belts and underground belts are placed.

What did you expect to happen instead? It might be obvious to you, but do it anyway!

- underground belts to be placed
- no unconnected belts to be placed

Does it happen always, once, or sometimes?

Always

Type 1: Type 2:
This is still an issue as of 2.0.44.

Why is this a duplicate / which post is this a duplicate of?

I searched the all post since Februar 3, 2024 (way before launch of Factorio 2.0) that contain the word "underground", but found none which was is similar.
Also searched for "Missing underground belt" (the error message) looking more far in the past, still no luck.

- most post are about placing underground belts issues while having them available in inventory
. this only happens if no underground belts in inventory :

- all issue posts are about missing exit belt or exit belt has wrong orientation- there are a really lots of duplicates of that, but this is post is different
. this either sets both or none of the underground belt ends :

This is indeed unique.

The issue only arises with the obstacle ending with a lateral running belt, two belts will place no underground ghosts and if it starts with non belt entity the entrance is placed at the drag starting point. It works correctly if you use ghosts placement:

The bug is not that the underground ghosts are not placed. That is indeed another bug. If I don't ghost build, ghosts must not be placed. Ghosts must be placed only when I ghost build. The otehr bug is the inconsisten gap size.

Ist shoudl leave exactly a gap before and after the belt to bridge if you have no undergrounds. It shall not place ghosts.