C# - Programmatically Log-off and Log-on a user

Question

I'd like to know if is there any way in C# to programatically log-in a Windows User Account?

We are currently developing an monitoring application and one of the feature is to be able to log-off the current Windows User and switch to another Windows User Account.

I have some few methods for Logging off, such as through API or Command Line. But what about logging-in a user account?

Um. Where is your code running? If you're running as an application as the current user, your application will be terminated by the log-off occurring. — Damien_The_Unbeliever, Mar 12 '10 at 07:35
@Damien_The_Unbeliever - Do you believe in Windows services? — Daniel Earwicker, Mar 12 '10 at 07:47
@Earwicker - of course, but I'd appreciate some clarity, given it was described as an application, not a service (although this may just be a terminology issue) — Damien_The_Unbeliever, Mar 12 '10 at 07:50
I'd like to make a custom LogonUI for my VMs. P/Invoke **will** be accepted. — , Jan 30 '21 at 21:34

score 3 · Answer 1 · answered Mar 12 '10 at 07:34

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You mean interactive?

Logoff, if anything fails, spawn a request to logoff.exe
Logon - nope. that is a GINA module that can go in front (look it up in google), but this is a very tricky beast to do. The security system in windows is pretty well isolated for obvious reasons (i.e. security).

I am not aware of anything you could do in C#.

http://technet.microsoft.com/en-us/library/cc780332%28WS.10%29.aspx

has some more details how user logon works.

answered Mar 12 '10 at 07:34

TomTom

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+1 It should be possible to replace the GINA module with your own. – Lieven Keersmaekers Mar 12 '10 at 07:41

score 1 · Answer 2 · answered Mar 12 '10 at 07:33

1

This might be what you're looking for...codesample

answered Mar 12 '10 at 07:33

hallie

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not sure I would consider setting up auto login relevant here. – TomTom Mar 12 '10 at 07:35
+1 - although that method also requires a reboot, it does work - the effect would be the same. – Daniel Earwicker Mar 12 '10 at 07:37
Whow. "althoug it requires a reboot, the effect would be the same" must be a new level of how low computer service can go. A solution reuiqring a eboot to change the logged in user is NOT the same. – TomTom Mar 12 '10 at 08:13
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Not an option in production systems. – Kobor42 Apr 10 '14 at 07:16
@TomTom To complainers. Yes, at the moment I do not like this method either. And oh man, I am also disappointed by not having found what I was looking for :P But then again, the above answer is not pointless at all. I was looking for a solution to a different though related problem. For switching active user the above solution may be rather helpful in some cases. In case there is no better way, the above is **a way**. Just because **you** do not need this answer or it does not fit your needs and because you are disappointed, does not mean the answer is bad. – Roland Pihlakas Dec 24 '16 at 22:30

C# - Programmatically Log-off and Log-on a user

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