Spinning mirrors

I was really irritated today when after uninstalling one edition of VS2015 and then installing another one, the setup program didn’t allow me to change the installation path. I manually uninstalled any leftover components from Add/remove programs and verified that the previous installation directory is empty. Still, the setup insisted that I install in the same location as the previous one. I searched the registry and sure enough, found some leftover keys with the old path. Most of them was here:

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components

At first I tried to clean them up manually but there were a lot of them, basically one entry for every previously installed file (of some components). As I said I uninstalled every VS2015 component so I didn’t care about deleting MSI entries. Finally I wrote a small C# program that did the trick:

using System;
using Microsoft.Win32;

namespace VsCleanup
{
    class Program
    {
        static int Main(string[] args)
        {
            Console.WriteLine("Enter the old VS path to purge from the registry:");
            string OldPath = Console.ReadLine().Trim().ToLowerInvariant();

            string RootKeyName = @"SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components";
            RegistryKey RootKey = Registry.LocalMachine.OpenSubKey(RootKeyName, true);
            if (RootKey == null)
            {
                Console.WriteLine("Unable to open registry, make sure to run as admin");
                return 1;
            }
            var SubkeyNames = RootKey.GetSubKeyNames();
            foreach (var SubkeyName in SubkeyNames)
            {
                var Subkey = RootKey.OpenSubKey(SubkeyName, true);
                var ValueNames = Subkey.GetValueNames();
                bool Delete = false;
                foreach (var ValueName in ValueNames)
                {
                    if (Subkey.GetValueKind(ValueName) == RegistryValueKind.String)
                    {
                        var Value = Subkey.GetValue(ValueName) as string;
                        if (Value.ToLowerInvariant().StartsWith(OldPath))
                        {
                            Console.WriteLine("{0}: {1}", SubkeyName, Value);
                            Delete = true;
                            break;
                        }
                    }
                }
                Subkey.Close();
                if (Delete)
                    RootKey.DeleteSubKeyTree(SubkeyName, true);
            }
            RootKey.Close();
            return 0;
        }
    }
}

Obviously, change the path to whatever you have/had (check in regedit manually first if not sure). It also works for VS 2013.

[Update: 2016-07-26]
Improved the code a bit. Also an important note: make sure to build the program as x64 if you’re on a 64-bit OS, otherwise you may get hit by registry redirection and it won’t work.

~ by omeg on January 2, 2016.