I am using a really cool Elven Greatsword mod, but I wanted to remove the grip, as I think the sword will look better without it. However, when I try to load the nif file in the meshes folder, nifskope won't load it. I get this:
""failed to load file header (version 14020007, 20.2.0.7)""
"failed to load nif from (file location)"

Any clue what's wrong?

(The mod hasn't been updated since early January, and its creator hasn't answered comments, so I was going to try to fix it myself.)

Maybe a silly question, but I guess you've downloaded and installed the latest version?

http://sourceforge.net/projects/niftools/files/nifskope/1.1.0/nifskope-1.1.0-rc6-i686-w32.7z/download