Runehamster: I have no texture mods installed (besides a robe replacer, and I believe that's only/mostly meshes), Siannah, and none that should have changed the path directory for textures or meshes.
I thought more of a mod pointing to specific new texture / meshes, but the game can't find them where they should be.
Runehamster: I'm also missing the mesh for the bow in the starting dungeon, which means something's gone funny with one of the major mods - WarCry, Fran's, or OOO. I'm perplexed.
Alright. For a search of "oblivion chest texture" Google comes with a link for OOO 1.31 on Planet Elder Scrolls on the first page. In the comments I read:
"To everyone whos having the magical yellow boxes of doom problem heres how you fix it: download 1.3 it contains all the textures missing from 1.31
it seems this patch is just a sort of addon to the other full mod"
I never played with the big overhauls, so can't really say if that's the case here.
Another potential problem could be load order.
You might want to try
FormID Finder to pinpoint which mod is causing it. Again, I don't have experience with it.
If all else fails, standard procedure: try & error. Start deactivating mods and see if the problem persists until you have your culprit.