Auto restart VB application after illegal kill by end process

user can illegal kill the second app also. I want to forbid any illegal kill my app

If you write as service and run on W2k or higher,

You should be able to let the system to restart your app.

Check the recovery tab on service properties

1. My App have to run in any Windows OS (9x,XP,NT,2K) so that services is not very good for me. Further more it is also can not forbid any illegal killing action.
2. for vinnyd97 solution: do you have any sample code for your solutions?
thank

http://www.thescarms.com/vbasic/StopReBoot.asp

Not to sound to facetous, but could you not have an app A than monitors app B, while app B is monitoring app A ?   Using ctrl-alt-del, a user can only close one app at a time.

Yes you are right Mr Nazdor. The sample in your link to restrict using TaskManager but it is not good for XP/NT/2K because it have to reboot to apply restriction.
I dont know how to monitor an app. from another one. Please give me a small example or some guide for it.
Thank

I am also working on a several programs that users might want to shut down illegally (security programs to prevent employees from accessing certain programs or children from getting on certain sites and such), so I have encountered the same problem. I have also been thinking along the lines of having two programs monitor each other, and each starts up the other if the other is shut down. One way to do this I can see is to have each program write a file to the disk, and the other erase it. For example, every 15 seconds or so, program A writes file ggg.txt (the name is arbitrary) to the Windows folder (or any other folder). Every 20 seconds program B checks to see if ggg.txt exists. If the file exists, Program B deletes it. If it does not exist, program B reruns program A. That way, if program A stops, the file is not there the next time that program B looks for it and program A gets restarted. Program B writes a similar file for A to look for. Likewise, program B writes a different file every 15 seconds, and Program A checks for this file every 20 seconds.
    I can see several problems with this, such as the fact that it consumes a bit of system resources, but it might be worth it if it is really important to keep the programs running.

The problem with two applications watching each other is that both could be killed within the alloted span of time leaving neither in a position to restart the other.  That may be unlikely, but it is possible.  After some thought I've come up with three other possibilities.  The first option is to use Windows' built-in task scheduler.  By scheduling the watching task, i.e. the program that's to check and see if the critical program is running, to run periodically it makes it more difficult for a user to find and dispose of it.  The watcher program runs just long enough to check and see if the production app is running.  If it's not, then it restarts it.  If it is, then it takes no action and terminates until the next scheduled run.  Option two will only work if the computers are all operating on a network.  The idea here is to use the Winsock control and have the watcher program running on a server or some other remote machine.  Periodically the central process can query user machiens to see if the required app is running.  If it isn't, then the central watcher app can start it remotely.  This approach is better in that it separates the watcher app from the required app and makes it impossible for a user to halt them both.  The downside though is that it requires bandwidth and, of course, won't be of any use for a PC not connected to the network.  The final possibility is to stick some code in the unload event of the production app to launch an app that'll restart it.  That'll only work if the app is shut down in a normal fashion though.  It won't work if the app is killed via Task Manager.  Maybe a hybrid approach that uses multiple methods to keep the production app running is best.

Here's a link to some code that lists running tasks.  One of them also includes code that is supposed to start a task remotely.  I can't vouch for whether it works or not.

http://www.freevbcode.com/ShowCode.Asp?ID=1861
http://www.andreavb.com/tip020014.html

  I have this same problem (people illegally killing the program), so I have come up with a solution. It does involve running two copies of the program, each of which monitors the other.
    When you first run the program, it runs another copy of itself. (When the program runs the second copy, it includes a command line to tell the second copy that it is a second copy.) The programs give themselves different title bars to distinguish between them. They then monitor each other using API calls. When one disappears, the other relaunches it. The monitoring is done with the timer control, which can be set to very short intervals, too short for anyone to kill both in time. I have tested this with half second intervals, and been totally unable to kill both. Someone who is really concerned can shorten it further. Since the programs use API calls, it is not as resource intensive as my original suggestion of using files to communicate. My solution works very well. I can post code if thuannc is still interested in this. Since I plan to use it in several programs, I have put all the code and global constants in one portable module, with directions where to put links to the subs. (I create security programs designed to limit access to computers.)

Hi all
I think BlueDeviFan have some good idea but I more prefer Leithauser solution be cause if I monitor app. remotely user easy to disconnect computer from network and then kill my app. I do it myself before (like vinnyd97 or Leithauser solution) but I have small problem with communicating beetween two app. Could you please give me your sample to learn more, Leithauser.
Thank