The Diablo 2 Wiki
The Diablo 2 Wiki archive is available for anyone looking for information on Diablo 2. All information here is pre-D2R but contains a lot of useful information that is still relevant. Updated sections for new D2R features can be found on the PureDiablo Diablo 2 section

Item Drop Hack

From Diablo 2 Wiki

Like most hacks, this one is spread by viruses in 3rd Party Programs. Players download a program alleged to be maphack, or a trainer, or some other sort of cheat, and riding piggyback is this little script. It sits quietly until it's activated by another player with the master end of the program, and then takes control of the victim's computer. The script moves the cursor to drop every equipped item on the ground, before closing or crashing Diablo II. Victims lose all of their items, either to theft by the other player, or simply to decay on the ground when the game crashes.

The following updates were taken from the Warnings page archives, and were written when this sort of program was new. It's still around, though most players on Battle.net these days have learned a bit over the years, and know better than to use 3rd party programs.

Item Dropper

March 26, 2002

We've had a lot of reports lately of people dropping items, especially when using programs that were supposed to dupe. The following is from the Blizzard Hacks team in a reply to us about it, after we forwarded them a mail with an address to a supposed dupe hack:

The program on the mentioned page basically will bring up your inventory screen, move over an item you are wearing, click to pick it up, moves off inventory screen and then clicks again to drop it. It does this to all item slots wear you equip items, it does it even if there is nothing in that slot. However from the ones I have seem it doesn't touch anything in the lower part of the inventory screen. Once it has done this it will shut down your computer so you get kicked out of the game. From here anyone in the game can go through and pick those items up.
The one on this page has been changed a bit so you now have to have the game running but older versions would ask you what resolution you are running the game in which is a dead give away. For those version you can run the program with out the game running and in about 15 seconds your mouse will start moving on it's own and the computer will shut off.
Blizzard Hacks Team

The moral of the story is that running 3rd party programs is almost always a bad idea, especially if they say they'll help you cheat; quite often they are just virus-infested, or trojans, or scams like this one.

There are also programs that will make anything you put into the trading window automatically click okay and transfer to the other player. Obviously the cheater has you DL that program and use it, saying it's a way to dupe, when they just want to steal your items with it. This and other trading rip offs are listed here.

A reader sent this in today:

A player offered the url of a program to dupe items. out of curiosity, i went to the site, and tried it on a mule in private game. it required me to run the prog from the web site location. further investigation revealed it is a simple automater prog made by hidden software. it can use scripts to automate the installation of programs and perform other tasks. quite funny to watch it used in this manner, as u have about one second to watch all ur items get dropped before computer lockup. funny on a mule, not too funny for a hi lvl char to get their hard earned items stripped. but that's the price for trying to cheat. tnx for ur informative columns and info.
Antonucci

Use your common sense. If someone says some program will do magical wonderful things for you with no risk or penalty, they are 99.9% sure to be lying to screw you, or they just don't know what they are talking about. This is true in life, BTW, not just on Battle.net.