Friend gave me a .exe file that he said was a program he needed help w/ for school...

[Warwithin]

...and all that came up was "UH OH YOU'RE BEING LOGGED OFF" before it logged off my computer. I'm not very tech savvy, but I did notice that the file was roughly 31kb and I checked my add/remove programs and there was nothing there that was new. What's the worst he could have done? I've got a lot of private information on my computer that I don't want a friend getting at because of what looks like an "April Fools" joke and am worried he might've installed something malicious.

[Indiglo]

Could be: http://www.wikihow.com/Make-a-Shutdown-Computer-Prank

[yurano]

This is why everyone should be running with an AV.

It also might be a joke .bat which only runs the shutdown CMD command.

[Butler to Baby Sloths]

windows key + r

type in

shutdown -a

You're welcome.

[Evil Inside]

Either it's just a prank, or he's not really a friend.

[Gandrake]

Either it's just a prank, or he's not really a friend.

or, if he got it over a messenger, he could have just been hacked

a year ago one of my friends MSN got hacked, now whenever i sign in he's pretending to be a woman and attempting to seduce me with his feminine charm so that i will click the suspicious link

[v2prwsmb45yhuq3wj23vpjk]

windows key + r

type in

shutdown -a

You're welcome.

This doesn't work for an untimed shutdown. Whenever I download something big from Steam or am doing something that will take awhile, I'll generally do it overnight and will set a shutdown timer. On the times I've forgotten to input a time and immediately attempted shutdown -a, it would say something like "Command 'shutdown' cannot be executed because windows is shutting down."

As for the OP, check the file to see if it's a batch file.

My bet is it's something like this:

msg * UH OH YOU'RE BEING LOGGED OFF
shutdown -s

Given that the file is only 31 KB that seems to be about the size a short message with a shutdown command would be (assuming he used a more complicated method of sending a message).

[Butler to Baby Sloths]

This doesn't work for an untimed shutdown. Whenever I download something big from Steam or am doing something that will take awhile, I'll generally do it overnight and will set a shutdown timer. On the times I've forgotten to input a time and immediately attempted shutdown -a, it would say something like "Command cannot be executed because windows is shutting down."

Even if you execute it from an elevated command prompt?

[v2prwsmb45yhuq3wj23vpjk]

Even if you execute it from an elevated command prompt?

Never tried it, always would just type it in Run because executing one command in Run was easier.

[Ryve]

I've got a lot of private information on my computer that I don't want a friend getting at

lol

Get a decent anti-virus. Be less gullible.

[bohapjut]

he probably planted your registry you'll need to wipe your hard-drive to get it off

[Grym]

See the friend tomorrow, greet him with a punch in the mouth, and warn him sending you any weird shit next time he will be greeted with a baseball bat.

On your way out also punch yourself for believing him, do NOT, accept .exe file from an untrusted source (like from your school officially, or major website and you know what you are downloading), a .exe from a friend I will never receive, I do not count friends as a trust worthy source.

[Peso]

Open notepad and copy paste this.

@echo off
echo UH OH YOU'RE BEING LOGGED OFF
ping localhost -n 4 >nul
shutdown /f /l

Save it as "Log.bat" to your desktop. Run it and if it's like your friends he probably converted the batch file to an executable application.