Question

I have a scenario where I need to launch an EXE from my .NET application, but I can’t get around the UAC prompt that pops up. The prompt is triggered even before the other EXE is launched – probably on the very call to Process.Start.

I use this code for launching the app:

            var info = new ProcessStartInfo(path, "params");
            info.Verb = "runas";
            try
            {
                Process.Start(info);
            }
            catch (System.ComponentModel.Win32Exception)
            {
                // Person denied UAC escallation
                return false;
            }

Both EXEs (my app and the other EXE) have this defined in their manifest:

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

How can I execute the other EXE without triggering a UAC prompt, and have it have the same access token as the calling application (so it can make changes to files in the app folder etc)?

Answer 1

To prevent a UAC prompt when launching a second EXE:

1) do not use Verb = "runas" — that will give you UAC every time

2) do not use setup-like filenames for your EXE. Here is the rule from MSDN:

Before a 32 bit process is created,
the following attributes are checked
to determine whether it is an
installer:

Filename includes keywords like
“install,” “setup,” “update,” etc.

Keywords in the following Versioning
Resource fields: Vendor, Company Name,
Product Name, File

Description, Original Filename,
Internal Name, and Export Name.

Keywords in the side-by-side manifest
embedded in the executable.

Keywords in specific StringTable
entries linked in the executable.

Key attributes in the RC data linked
in the executable.

Targeted sequences of bytes within the
executable.