Failed to load mods: The given sprite rectangle (left_top=0x0, right_bottom=120x120) is outside the actual sprite size (left_top=0x0, right_bottom=120x64).
If this is being used as an icon you may need to define the icon_size property.
See the log file for more information.: base/graphics/icons/gun-turret.png

Factorio 2.0.72

What other mods do you have enabled? Because I don't get this error while loading just Howitzer.

I'll see if I can isolate what it is. My guess was the Space Age HD textures packs, but I'll see if I can figure it out.

Found it, it conflicts with this one:
https://mods.factorio.com/mod/achievements_plus_plus_plus_plus

My guess is that when it pops up to show you the achievement, it wants an icon in the right size.

Oh strange, I'll look into it.

I've had the same startup error recently and I don't have the achievement mod listed above. The error seems to occur when loading sprites and it lists the default gun turret icon as not the "correct" size. Maybe an icon is either missing or has weird dimensions (like 0x0 for example). Not too sure about anything deeper than that but I can post the exact error message if that would help diagnose the problem. Also sorry for the slight necropost lol

EDIT: Just reread the top post and I totally missed that entire message whoops. I have the same error. :)