Question

My app needs to set up a SQL alias when it runs if it detects the alias is not set up. Right now I have it generate a temp Reg File and and run it through regedit.exe, however because my app is 32 bit (it must be as I am interoping with some 32 bit dll’s that I can not get 64 bit versions for) windows is doing redirection when I run regedit to the version %windir%\SysWow64\regedit.exe instead of %windir%\regedit.exe.

This causes the keys I attempt to write to [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo] to be redirected to the 32 bit sub folder, and my explicit writes to the 32 bit sub-folder, [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\MSSQLServer\Client\ConnectTo] I have no clue where they are going.

Normally to get around this you would just use %windir%\sysnative\xxxx.exe but sysnative redirects to the System32 folder not the root windows folder, which is where regedit resides.

Is there a way to solve this issue without writing a custom program to elevate and do it itself?

---

Here is my current code, that is failing.

static void CreateAliases()
{
    using (var baseKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32))
    {
        using (var key = baseKey.OpenSubKey(@"SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo"))
        {
            CheckKeys(key);
        }
    }
    try
    {
        using (var baseKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64))
        {
            using (var key = baseKey.OpenSubKey(@"SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo"))
            {
                CheckKeys(key);
            }
        }
    }
    catch
    {
        //Catch failues if it is 32 bit only.
    }
}

private static void CheckKeys(RegistryKey key)
{
    //check to see if the key exists.
    if (key == null)
    {
        AddKeys();
        return;
    }

    var value = key.GetValue(@"wi\sql2008");
    if (value == null || value.ToString() != String.Concat("DBMSSOCN,wi,", Properties.Settings.Default.wi_sql2008Port))
    {
        AddKeys();
        return;
    }

    value = key.GetValue(@"wi\sql2005");
    if (value == null || value.ToString() != String.Concat("DBMSSOCN,wi,", Properties.Settings.Default.wi_sql2005Port))
    {
        AddKeys();
        return;
    }
}
static private void AddKeys()
{

    string file = System.IO.Path.GetTempFileName();
    using(StreamWriter sw = new StreamWriter(file))
    {
        sw.WriteLine("Windows Registry Editor Version 5.00");
        sw.WriteLine();
        sw.WriteLine(@"[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\MSSQLServer\Client\ConnectTo]");
        sw.WriteLine(String.Concat("\"wi\\\\sql2005\"=\"DBMSSOCN,wi,", Properties.Settings.Default.wi_sql2005Port,'"'));
        sw.WriteLine(String.Concat("\"wi\\\\sql2008\"=\"DBMSSOCN,wi,", Properties.Settings.Default.wi_sql2008Port,'"'));
        sw.WriteLine();
        sw.WriteLine(@"[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo]");
        sw.WriteLine(String.Concat("\"wi\\\\sql2005\"=\"DBMSSOCN,wi,", Properties.Settings.Default.wi_sql2005Port, '"'));
        sw.WriteLine(String.Concat("\"wi\\\\sql2008\"=\"DBMSSOCN,wi,", Properties.Settings.Default.wi_sql2008Port, '"'));
    }

    WindowsIdentity identity = WindowsIdentity.GetCurrent();
    WindowsPrincipal principal = new WindowsPrincipal(identity);
    bool IsAdmin = principal.IsInRole("BUILTIN\\Administrators");

    string regedit;

    if (Environment.Is64BitProcess)
    {
        regedit = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.System), "regedit");
    }
    else
    {
        regedit = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Windows), "sysnative", "regedit"); //regedit.exe does not exist in sysnative.
    }

    if (IsAdmin)
    {
        var proc = Process.Start(new ProcessStartInfo(regedit, String.Concat("/s ", file)));
        proc.WaitForExit();
    }
    else
    {
        MessageBox.Show("Updating registry keys for WI alias, this must be run as administrator");
        var proc = Process.Start(new ProcessStartInfo(regedit, String.Concat("/s ", file)) { Verb = "runas", UseShellExecute = true });
        proc.WaitForExit();
    }

    File.Delete(file);

}

Here is the temp file that is being generated.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\MSSQLServer\Client\ConnectTo]
"wi\\sql2005"="DBMSSOCN,wi,49224"
"wi\\sql2008"="DBMSSOCN,wi,49681"

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo]
"wi\\sql2005"="DBMSSOCN,wi,49224"
"wi\\sql2008"="DBMSSOCN,wi,49681"

Answer 1

I would look into creating a server alias using the SMO ServerAlias class instead, then you don’t have to deal with the registry access yourself.