windows user login

Hello! I was wondering if anyone had ever tried to log into windows with an arduino. My goal, at this point, is to press a press a button through the arduino to bypass the username and password input boxes. I want to do this simply as a proof of concept and things like RFID user login, keypad login, clapper login, and similar could come next.

I understand that I will have to use the serial interface and have even tried programs like gobetwino.

My questions/problems: -Will gobetwino be able to run even with no user logged in (waiting for the login input) If not, is there a better serial interface that you know of? -How exactly could I log in? I had anticipated something as simple as a batch file but it seems like it might be harder. Maybe wsh? Is there a simple method that you know of? Java/C++/something?

Thank you all, -Adam

i dont see anything impossible here... It is possible to skip the windows logon via software (e.g. and i belive to remember ways to hook into the auth process to implement own ways of logging on. I had once tried to login via putting a smiple USB Stick with a file on it into the computer, but had a problem simewhere along that..

So, IF the Com driver is present at logon it should be doable.

if you don't want to compromise windows too much maybe something like a keyboard interface would be best. or a remote login over ethernet.

what are you thinking of exactly? what does the windows box do after you log in?

Thanks for the quick reply.

I agree, it should be possible!

Do you have any kind of documentation that you created or were following for your project? Is anything left? Code? What kind of approach were you trying.

Your post led me to googling other things that seem more related to what I want, but at the same time, I have not found one single case where someone was using an arduino, an executable, or a com port to log in.

You could emulate a keyboard but would need some way to detect the login dialog.


RE: bill2009

By compromise do you mean security compromising? If so, I am perfectly fine with that for now. My home machine is in no danger of being hacked through this method. It doesn't even have a password now!

"Keyboard interface" Actually I had considered that. Use the arduino to output the username, a tab, the password, and enter.

The goal is to have the machine log in as if a user sat down and typed in their username and password in the windows logon box.

The process I had thought of (though I am not attached to it at all) is: 1) press button 2) arduino sends serial "its ok to login" message 3) program like gobetwino catches it 4) gobetwino launches "logintowindows.exe" 5) User is now logged in without typing username/password

I have recently been looking also at the LogonUser function, but it seems like most people have major problems with it. Also, it seems to be tailored to logging in behind the scenes to just start a process or something instead of launching the entire windows user environment.

You can replace the Windows GINA ( with your own, which listens to a communications port.

It wouldn't be much work, the SDK has some samples - you could just add a COM port open, series of reads, etc.

Note that XP/2003/2000 are the only versions that support a replacable GINA, according to the docs that I have found.