How to make world.img back to its default???

[Rambo7]

I had reskin a lot of texture & import a lot of model,
and I totaly forget which model (.nft &.nif) file that I already reskin & import,
Now my game keep crashing, & I want to set make my world.img back to its default before any skin or import mod that I add there

Anyone know how to do it??
I have the world.img & world.dir backup, & I just simply replace my world.img & world.dir in my bully game with the backup data.
But still the same it keep crashing
Any help appreciate,
Thanks

[Al Arlington]

What OS are you running? Virtual Store may be causing this problem.

[Rambo7]

I use windows 7,
and I think I know, which model make my game chrash, it is the spudgun /spudg.nif, which I am trying to import it with some sniper gun
but when I  play new game the games working, cause there is no spudgun in chapter 1 game play
I already try to replace the spudg.nif(the error one) with my backup .nif file manually from the imgtools2 but still the same when there is spudgun my game crash,
Do I need to replace the game anim file, cause the spudgun I'm imported before had animation attached to the .nif file