Is this a typical E-STEP issue?

[redbeardprint]

Looking at the split on the right, it looks like the slicer just said there should not be any wall.
I just had this happened with some new slicer software. It turned out that the software doesn't think that is thick enough so it makes it an open.
There was an option in the slicing settings that expressed "fine detail" and the problem went away.
Different printer and slicer but very similar results.

Thanks for that.
Yeah it's so strange. When I run the GCODE in the slicer (Cura 4.0.0) and play through each layer it looks like it prints as per normal during those layers. There's no difference between the layers below and above it, it's a storage tray with even walls all the way up - just a couple of locating lugs just below the 'missed layer'.
I tried again last night after calibrating and adjusting my ESTEPS as well as my X axis gantry was not parallel. I didn't have time to do a test last night but will try tonight.
I have 'print thin walls' turned on.
I'm not sure if Cura isn't working for me or if it's my printer or settings or a mix of the lot. But I think I've got the latter dialed in so might try another slicer. Any suggestions on a free one? Thinking I might try Slic3r.

Cheers
Hunt