So I already know that deleted navmeshes can cause CTDs in large loadorders.
But why can't I just remove the deleted navmesh entry in xEdit? Would that cause issues except potential pathing issues for NPCs?
Posted Nov 8, 2018, 10:40 PM UTC
If an NPC, or rather, anything tries to reference that deleted navmesh the game will CTD.
Pretty much all I know
But if I remove the edit, there is no longer a deleted navmesh that another mod can reference.
Then you'll have two navmeshes sitting on top of each other the new one and the original which results in... odd things happening with NPC's. It'll fix the CTD's but NPC's will get rooted to the spot, unable to exit through doors, all kinds of broken behaviour.
It doesn't matter.
If an NPC or another mod references that navmesh, the game will CTD
It doesn't require a large loadorder to generate a CTD. All that is needed is 1 mod to touch the area in which the deleted navmesh occupied.
Theres an issue with the CK as it stands it'll delete existing usually vanilla navmeshes and replace with a new one. The worst part about this is it doesn't tell you its doing it usually the first time you're aware of it is when you clean the mod via xEdit and it reports deleted navmeshes. Nukem's CK Fixes aims to stop this happening I think, havn't tried it myself.
If you know what you're doing you can fix it yourself in xEdit if its a simple replacement just identify the replacement navmesh make a note of the form i.d. of the deleted one, remove it with xEdit (delete the record from the mod) then change the form i.d. of the replacement to that of the original navmesh, check a few boxes to confirm and update etc, you're done.
n.b. the tricky bit is when a single deleted navmesh is replaced by two or more new versions then it becomes a headache...
You can't just undo the deleted record. You need to check to be sure there isn't a duplicate record, otherwise the game will get confused and NPCs won't be able to navigate properly.
This guide should get you through the process properly: https://afkmods.iguanadons.net/index.php?/topic/3337-skyrim-fixing-navmesh-deletion-using-tes5edit/
That said, it's best to report those to their authors and then not use those mods until they fix them for everyone.