Request Windows Vista Uac Elevation If Path Is Protected

Request Windows Vista UAC elevation if path is protected?

The best way to detect if they are unable to perform an action is to attempt it and catch the UnauthorizedAccessException.

However as @DannySmurf correctly points out you can only elevate a COM object or separate process.

There is a demonstration application within the Windows SDK Cross Technology Samples called UAC Demo. This demonstration application shows a method of executing actions with an elevated process. It also demonstrates how to find out if a user is currently an administrator.

How to prevent Vista from requiring elevation on patch.exe?

From:

http://social.msdn.microsoft.com/Forums/en-US/windowsgeneraldevelopmentissues/thread/bf4f7dfa-5553-41d3-9c8e-311ee4a88599/

If you can add a manifest to the
affected executable declaring a
requestedExecutionLevel of 'asInvoker'
it should stop prompting.

Associated guide on UAC architecture and converting existing applications so they work correctly (near the bottom fifth of the page):

http://technet.microsoft.com/en-us/library/cc709628.aspx

Lastly, how to write such a manifest:

http://www.google.com/search?q=writing+a+uac+manifest

-Adam

Windows 7 and Vista UAC - Programmatically requesting elevation in C#

WindowsPrincipal principal = new WindowsPrincipal(WindowsIdentity.GetCurrent());
bool hasAdministrativeRight = principal.IsInRole(WindowsBuiltInRole.Administrator);

if (!hasAdministrativeRight)
{
    RunElevated(Application.ExecutablePath);
    this.Close();
    Application.Exit();
}

private static bool RunElevated(string fileName)
{
    //MessageBox.Show("Run: " + fileName);
    ProcessStartInfo processInfo = new ProcessStartInfo();
    processInfo.Verb = "runas";
    processInfo.FileName = fileName;
    try
    {
        Process.Start(processInfo);
        return true;
    }
    catch (Win32Exception)
    {
        // Do nothing. Probably the user canceled the UAC window
    }
    return false;
}

how can i replace a file asking for elevation

You can start another process with elevated permissions, using the runas verb when starting the process.

Something like this:

ProcessStartInfo info = new ProcessStartInfo("pathtoyourexecutable.exe");
info.Verb = "runas";
Process process = new Process();
process.StartInfo = info;
process.Start();

I don't think there is any way to get out of needing to create a new process, it can't be done at the Thread level. You could use Out-of-Process COM objects, but that's even more trouble.

How to display UAC prompt for file save to restricted location using c#?

You need to do what Windows does. And spawn a new process which will run with elevated rights. There are no shortcuts here. The token that is allocated when a process starts is what determines what rights the process has. That token cannot be changed after the process has started. If you need to elevate, you need a new process.

I've seen lots of answers around this topic that involve spawning a new process with elevated privileges using 'runas'. Also, it seems like this can be done by impersonating another user. From what I understand, both of those methods require a user to provide user credentials.

No that's not the case. If the current user is not an admin, then the UAC dialog will prompt for new credentials of a user that does have admin rights. That's the over-the-shoulder UAC dialog. On the other hand, if the current user is an admin then they just get the consent dialog. That's the dialog that's shown on the secure desktop and just asks for you to click Continue.

The one thing that Windows components can do that you cannot is start a process elevated without showing you the consent dialog. That happens on Windows 7 only (not on Vista), and only if you have the UAC setting at the new Default setting that was added in Windows 7. That's how Explorer is able to show the dialog that you included in the question and then start an elevated process to do the copying without showing the consent UAC dialog. Only Windows components are granted that ability.

But the bottom line is that you need to start a new process that runs elevated. Using the runas verb is the canonical way to do it.

Creating folders in UAC-protected areas

This is usually done by creating a separate process with the "runas" verb:

• ShellExecute example
• C# example

This process can perform any operations which require elevation.

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