I did a list of essential developer tools some years back. A lot of water has run under the bridge since then, so I feel it is time for an updated version.
- Visual Studio 2013/2015
- JetBrains dotPeek (current version) [https://www.jetbrains.com/decompiler]
- GhostDoc (current version) [https://visualstudiogallery.msdn.microsoft.com/46a20578-f0d5-4b1e-b55d-f001a6345748]
- BeyondCompare [http://scootersoftware.com/download.php]
- Fiddler [http://www.telerik.com/fiddler]
- Notepad ++ [https://notepad-plus-plus.org]
- Terminals [https://terminals.codeplex.com]
It doesn't look like much and it honestly isn’t, but it is the focused and essential list of tools you need in your toolbox as a .NET developer/troubleshooter.