The AutomaticUpdater control is included with wyBuild and it can be included with your applications royalty free. It works with Visual Studio 2005 through Visual Studio 2019 and .NET 2.0, 3.0, 3.5, 4.x (i.e. 4.0, 4.5, etc.). Download wyBuild now. It works with all .NET languages (C#, VB.NET, etc.)
If you're not making a .NET app then you can still use wyUpdate to update your app. Read one of the following articles:
After you've added the AutomaticUpdater control to your application, it's a simple matter of including wyUpdate.exe & client.wyc files to your application and releasing it to your users.
Watch the video intro
Get the C# source code
To top it all off, the AutomaticUpdater is completely open source (LGPL license).