Back in my senior year of high school during Spanish class I naively used NET SEND to send a message to one of my classmates. The only problem was that I failed to specify the user in the command and instead used *. This ended up sending a message to all computers in the school district.

I remember the computer administrator coming into the class saying “Are you aware one of your students is sending messages to the entire school district?” My heart sank.

I ended up getting in-school suspension. Considering this was my first ever “offense” in school, I felt like a badass going out with a bang.

A classmate did the same, although the outcome was far worse.

We studied at university in the medical faculty, which happened to be housed in the academic hospital. We found out the hard way that the network was not segregated, his netsend command crashed all the ICU terminals...

Just that the guy isn't to blame. That's like saying "By switching off the lights in the break room I shutdown the power in all the operation rooms"

Same, apart from the suspension. On my first computer science class. That was... not fun.

The professor classified me as the annoying kid, until I surpassed his expectations with the first programming excercises :P

I did the same in 8th or 9th grade, but on purpose and I sent a crap ton. The admin stormed in and yanked the laptop out of my hands and revoked my PC privileges for ~3 months. Fun.

I caused havoc in high-school with that. And finding a way of executing binaries inside Novell's Netware thing, via the "Open" dialog within any Office application's Visual Basic macro editor haha

Renaming executables to explorer.exe worked with the application whitelisting solution my school implemented.

That's how we ended up with 8-player age of empires 2 deathmatches after hours ;)

I created a directory with alt+255. It was an unprintable character and showed up last in any dir listing. At most it added an extra new line. That’s how I was one of the only students whose apps didn’t get caught during auditing.

That brings me back. All .exe were blocked.

However it turned out that you could rename them .bat or .cmd and they would execute just fine.

I think Doom 2 multiplayer was extra fun because of the added need to be aware not just of in-game enemies but also the need to be aware of the teacher and be ready to instantly quit at any moment.

Haha, me too :D

Wrote a batch script that used a wildcard - it took them a while to find it and I was very lucky the only 3 persons who knew who it was wouldn't tell anyone. One was a teacher and I am thankful until today that he didn't screw up my life with telling this.

Hah! I did this one at a call center job back in the day, not believing that their sysadmins would possibly leave it open.

I was wrong. I did something like "NET SEND lol" and it sent out a popup to every workstation on the network. Hundreds of them.

Good times.

Once students learnt the NET SEND command, the school was plagued with popups... IT security is an evolving thing I guess.

I had so much fun with that back in school. Our machines were running Win NT 4.0 and and the computers were labelled with a the network name. So I would check the names of the machines my friends were on, or the whole class if I was feeling bold and then create a batch file to send them hundreds of messages.

Back in 2002 or so, NET SEND was a vector for spammers to send messages over the internet as well.

https://tweaks.com/windows/37362/stop-net-send-spammers/