Viewer crashes out

[cympatheey]

Okay when Im just working on the model In o2 (lods and such) i can see the model okay just fin in the viwer when I strat applying textures is when everything craps up as soon as i load the texture scale it up make it fit nicely and hit b to apply the gun texture the thing crashes out wierd thing is that that It only does it on the gun texture and that I made the flash side texture works just fine but all the other ones are crap and they crash it Out?http://forums.bistudio.com/oldsmileys/rock.gif? Anyone know how to fix this or did I just set o2 Up wrong or something?
Thanks
/CymPatheeY