Requesting Administrator Privileges At Run Time

Requesting administrator privileges at run time

Not quite, but you can do the opposite—you can drop privileges if you already have them. So, you can have your program start out running as an Administrator, using one of the methods listed by Kate Gregory. Then, drop your unneeded privileges; see Dropping privileges in C++ on Windows for how to do that.

How to request administrator permissions at runtime?

As far as my research (May 9, 2021) when, there is no possible way to extend the privileges of the current program. Also see @Flydog57's comment:

You can't. If you want to get the OS UAC prompt asking the user to use his/her admin mojo when running the program, only the OS can do that for you, and it is done before your code starts. When a program starts, it gets a token that identifies the user and his/her permissions and privileges. When UAC is enabled, an admin user has a non-admin token and an admin token. As a program starts it gets one of those. Once the program starts, the token cannot change. If you need to do this, start up another process with a different token.

The only logical solution is to start a new executable/process whole together with elevated privileges. With C#, you can use System.Diagnostics.Process.

However, this might change (I have no sources, but it's a possibility) in the future.

C# How to get admin privileges AT RUNTIME

You can't change the privilege level of a currently running process. You CAN launch a new process, asking for elevated permissions. Process.Start() supports the flag "runas".

        using (Process configTool = new Process())
        {
            configTool.StartInfo.FileName = "foo.exe"
            configTool.StartInfo.Arguments = "--bar";
            configTool.StartInfo.Verb = "runas";
            configTool.Start();
            configTool.WaitForExit();
        }

See Elevating process privilege programmatically?

You could separate functions of your application into a second executable, or re-launch your application with elevated permissions with "runas".

Requesting Administrator privileges during runtime

This information is written in the exe file manifest. You must use the requestedExecutionLevel field (but not sure about that - try setting it to highestAvailable and see if it does what you need). See for example here for more information (somewhat older article but still valid): http://blogs.msdn.com/b/cjacks/archive/2006/09/08/exploring-manifests-part-2-default-namespaces-and-uac-manifests-in-windows-vista.aspx

There are tools in Visual Studio which allow you to embed your own manifest or even just edit it. Also there is a tool written in Perl ( http://metacpan.org/pod/Win32::Exe::Manifest ).

EDIT: see this article for more info: http://www.codeproject.com/Articles/66259/Requesting-Admin-Approval-at-Application-Start.aspx

How can I give admin permission to an application during run time?

I put the following command in a .bat file
SUBINACL /SERVICE /GRANT=S-1-5-32-545=TO > %1
and ran the bat file while installing the application from setup.exe.
It resolved the issue.
Thanks for your comments @Harry Johnston

How does a program ask for administrator privileges?

There are a number of methods depending on your needs. Some details are given in the application developer requirements for UAC.

1. Include a UAC manifest that causes your program to require administrator privileges at startup.
2. Use one of the suggested methods for invoking an elevation to run out of process. One of the nicest is to use the COM elevation moniker and CoCreateInstanceAsAdmin to call methods on a COM object running as an administrator. This is possibly tricky to get working in VB.Net. I got it working ok in C++ though
3. Another ok method is to isolate the parts of your code that need admin privileges into an application that uses a UAC manifest to require admin privileges. Your main app does not need to run as an admin in that case. When you require admin privilegese, you would invoke the external application.

How to request administrator permissions when the program starts?

Add the following to your manifest file:

<requestedExecutionLevel level="requireAdministrator" uiAccess="false" />

You can also use highestAvailable for the level.

Look here about embedding manifest files:

http://msdn.microsoft.com/en-us/library/bb756929.aspx

PS: If you don't have a manifest file, you can easily add a new one:

In Visual Studio, right click project -> Add Item -> Choose
Application Manifest File ( under General for Visual C# items)

The added file will already have the above part, just change the level to requireAdministrator from asInvoker

---

Related Topics