Starting a process from inside a windows service

[Timothy Shih]

Hi,

I am trying to start a process from inside a .NET service. The process is a
simple GUI app, the service will start up the GUI and then stop itself. The
service starts the app, but no GUI appears. However, I can see the
application running in the task manager. I made sure that CreateNoWindow was
set to false and still no GUI appears. If i run the application by double
clicking on it, the GUI appears fine. Here is the code:

Process p = new Process();
p.StartInfo.FileName = _basedir + "DbUpdate.exe";
p.StartInfo.WindowStyle = ProcessWindowStyle.Normal;
p.StartInfo.CreateNoWindow = false;
p.StartInfo.UseShellExecute = true;
p.Start();

Essentially, I am checking the version of a database and if it is not the
correct version, I want to stop the service and start up the updating
utility. The service runs, starts the process, and exits as expected, but
the GUI does not appear, except as a process in Task Manager. If it matters,
I am executing the code through a class using remoting and it is in the
constructor of the class. Also note that the service exits immediately after
starting the process, although I did not think that would be a problem.

If anyone has any insight into the cause of this problem, it would be very
helpful to me.

-Timothy Shih

[Nicholas Paldino [.NET/C# MVP]]

Timothy,

You have to check the properties of the service, and make sure that the
checkbox that says "allow service to interact with desktop" is checked.
However, this is a bad idea, because you can not guarantee that you always
have an interactive user session to show a GUI for.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Timothy Shih" <ts***@sensicast.com> wrote in message
news:eR**************@TK2MSFTNGP09.phx.gbl...

Hi,

I am trying to start a process from inside a .NET service. The process is a simple GUI app, the service will start up the GUI and then stop itself. The service starts the app, but no GUI appears. However, I can see the
application running in the task manager. I made sure that CreateNoWindow was set to false and still no GUI appears. If i run the application by double
clicking on it, the GUI appears fine. Here is the code:

Process p = new Process();
p.StartInfo.FileName = _basedir + "DbUpdate.exe";
p.StartInfo.WindowStyle = ProcessWindowStyle.Normal;
p.StartInfo.CreateNoWindow = false;
p.StartInfo.UseShellExecute = true;
p.Start();

Essentially, I am checking the version of a database and if it is not the
correct version, I want to stop the service and start up the updating
utility. The service runs, starts the process, and exits as expected, but
the GUI does not appear, except as a process in Task Manager. If it matters, I am executing the code through a class using remoting and it is in the
constructor of the class. Also note that the service exits immediately after starting the process, although I did not think that would be a problem.

If anyone has any insight into the cause of this problem, it would be very
helpful to me.

-Timothy Shih

[Dilip Krishnan]

You may want to consider a ms task/job instead. Ideally a service
shouldnt have a gui dependency
Timothy Shih wrote:

Hi,

I am trying to start a process from inside a .NET service. The process is a
simple GUI app, the service will start up the GUI and then stop itself. The
service starts the app, but no GUI appears. However, I can see the
application running in the task manager. I made sure that CreateNoWindow was
set to false and still no GUI appears. If i run the application by double
clicking on it, the GUI appears fine. Here is the code:

Process p = new Process();
p.StartInfo.FileName = _basedir + "DbUpdate.exe";
p.StartInfo.WindowStyle = ProcessWindowStyle.Normal;
p.StartInfo.CreateNoWindow = false;
p.StartInfo.UseShellExecute = true;
p.Start();

Essentially, I am checking the version of a database and if it is not the
correct version, I want to stop the service and start up the updating
utility. The service runs, starts the process, and exits as expected, but
the GUI does not appear, except as a process in Task Manager. If it matters,
I am executing the code through a class using remoting and it is in the
constructor of the class. Also note that the service exits immediately after
starting the process, although I did not think that would be a problem.

If anyone has any insight into the cause of this problem, it would be very
helpful to me.

-Timothy Shih

--
Regards,
Dilip Krishnan
MCAD, MCSD.net
dilipdotnet at apdiya dot com

[Elp]

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in
message news:%2****************@TK2MSFTNGP09.phx.gbl...

Timothy,

You have to check the properties of the service, and make sure that the checkbox that says "allow service to interact with desktop" is checked.
However, this is a bad idea, because you can not guarantee that you always
have an interactive user session to show a GUI for.

....and if your service is running under the Local System account (which is
the case most of the time unless you change it to a more restrictive
account), the GUI application you are trying to launch will have all the
Local System account right, which means even more rights than the
Administrator account! Definitely no a good idea.