Solved High resolution

@jmh033089, you already have an answer here. There may be a few mods who do it, however most servers don't and neither do we for obvious reasons.
You can't force everyone on the server to play on the same resolution so there will definetly be a significant unfair advantage of using a higher resolution hack, mod, etc (this is a hack) because you will be able to see further than your opponent can when dueling and therefore you will be able to kill him without even seeing you. In terms of pvm you could literally cast something like blizzard and the mobs won't even move so you will be able to attack and kill monsters way before they can see or attack you as their radius will be using the default game resolution and there will also be various various mapping problems regarding buttons positioning, possible performance drop and things like that. You can use glide wrapper instead but high res mod stuff are not compatible and not allowed, besides they won't really make a huge difference in terms of graphics anyway since we're talking about a 17 years old game.

 

http://forum.europebattle.net/threads/d2multires-mod-is-legal-or-not.539892/#post-787384