Due to a sudden bit of lag when building, I accidentally placed a window at ground level (so half the window was at floor height, and half one block above).
When the building was complete, including the hole for the frame, my carpenter came along to place the window. When placed, the carpenter then became frozen. It was as if the AI code wanted him to remove a ladder, when there wasn’t one.
thanks for the descriptive bug report @Goose… those repro steps go a long way towards helping resolve the issue…
any chance you can toss up a screenshot as well?
I forgot to take a shot of the stuck carpenter last night, sorry. Loading the game this morning, the guy was wandering free but there is a ladder where he was stood, that never gets removed. Everyone can walk through that corner (near the chairs) too:
I’m not sure if it’s related, but even though there are plenty of frames in storage, the workers will not touch them any more. I also can’t place any items near any empty windows. For example, I tried to place beds next to the empty windows at the top of this image, but the workers never do it:
no worries… thanks for the follow-up… 
so, selecting the ladder, you dont have the UI option to remove it, or when you select it, no units complete the order?
It’s OK, I spend my working day tracking badly-reported bugs. I can’t complain about those if I do a rubbish job here.
Nope, no option to remove it. I built a few ladders myself, and the option to remove those appears. This ladder brings nothing:
