Restarting a Windows Service with C# under Vista when User Account Control is Enabled

[gourmet]

Hello!

I need to restart the "Windows Audio Service" (audiosrv) via C#. I'm
using the ServiceController Class to do this.
It is no problem under XP and no problem under vista if UAC is
disabled.
But with enabled UAC i'm getting a "access refused" exception.
I also tried to do it via console with "net start ..." but the same
error appears.
Three questions:
1. Is it possible to restart the "windows audio service" if UAC is
enabled ?
2. Why does the exception occur? If I do some other stuff, e.g.
starting regedit via Process.Start() the user gets asked if he really
wants that. I would expect the same behaviour for restarting
services.
3. If it's not possible at all: Can I find out programmatically
whether UAC is enabled?

Thanks and excuse my bad english!

 

[Willy Denoyette [MVP]]

Hello!

I need to restart the "Windows Audio Service" (audiosrv) via C#. I'm
using the ServiceController Class to do this.
It is no problem under XP and no problem under vista if UAC is
disabled.
But with enabled UAC i'm getting a "access refused" exception.
I also tried to do it via console with "net start ..." but the same
error appears.
Three questions:
1. Is it possible to restart the "windows audio service" if UAC is
enabled ?

Yes when running as full "Administrator". That is start the console (cmd interpreter) by
right clicking "Run as Administrator".

2. Why does the exception occur? If I do some other stuff, e.g.
starting regedit via Process.Start() the user gets asked if he really
wants that. I would expect the same behaviour for restarting
services.

The exception occurs because you are running as a standard user, only admins can start, stop
.... services.
If you want the same behavior you'll have to insert a "manifest" in your executable file.

<?xml version="1.0" encoding="utf-8" ?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
<assemblyIdentity version="1.0.0.0"
processorArchitecture="X86"
name="someExecName"
type="win32" />
<description>Program description</description>
<trustInfo xmlns="urn:schemas-microsoft-com:asm.v3">
<security>
<requestedPrivileges>
<requestedExecutionLevel level="requireAdministrator" />
</requestedPrivileges>
</security>
</trustInfo>
</assembly>

To add above manifest to the executable assembly, you have to run mt.exe like this;

mt -manifest somename.exe.manifest -outputresource:somename.exe;#1
PS change the someExecName and Program description to suit your needs...

3. If it's not possible at all: Can I find out programmatically
whether UAC is enabled?

See above.

Willy.

 

[Willy Denoyette [MVP]]

Yes when running as full "Administrator". That is start the console (cmd interpreter) by
right clicking "Run as Administrator".

The exception occurs because you are running as a standard user, only admins can start,
stop ... services.
If you want the same behavior you'll have to insert a "manifest" in your executable file.

<?xml version="1.0" encoding="utf-8" ?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
<assemblyIdentity version="1.0.0.0"
processorArchitecture="X86"
name="someExecName"
type="win32" />
<description>Program description</description>
<trustInfo xmlns="urn:schemas-microsoft-com:asm.v3">
<security>
<requestedPrivileges>
<requestedExecutionLevel level="requireAdministrator" />
</requestedPrivileges>
</security>
</trustInfo>
</assembly>

To add above manifest to the executable assembly, you have to run mt.exe like this;

mt -manifest somename.exe.manifest -outputresource:somename.exe;#1
PS change the someExecName and Program description to suit your needs...


See above.

Willy.

To further clarify:
save the above manifest in a file called "some.exe.manifest", where someApp is the name of
your executable file.
Say you have "audioCntrl.exe", then you could name your manifest audioCntrl.exe.manifest"
and run mt.exe like:

mt -manifest audioCntrl.exe.manifest -outputresource:audioCntrl.exe;#1

Willy.
PS. type mt /help from the command line for more detailed help on mt.

 

[gourmet]

Thank you very much!

I will try that manifest stuff on friday and will let you know if it
worked for me...