Install Notepad++ from https://notepad-plus-plus.org/download/
Start Notepad++, either from the installer (when it has finished), the Start Menu or the Windows Explorer Context Menu to edit a file. As of version 6.8.6 the default installer includes the following plugins: Converter 3.0, MIME Tools 1.9, NppExport 0.2.8, Plugin Manager 1.3.5, interestingly DSpellCheck 1.2.14 and NppFTP 0.26.3 are no longer included, they used to be. Clearly there are plenty more plugins that can be added, however, as with all software, don't install every plugin you find, just pick what you really need. My recommended plugins are below.
It is worth noting that you should run the installer as "Administrator" by right clicking the installer and selecting "Run as Administrator". On a Windows Server 2008 R2 box, I found that just running it meant the context menu did not work in Windows Explorer, re-installing with "Run as Administrator" got this working. This was not the case with Windows Server 2012 R2 and Notepad++ 6.8.2.
I also found that this still did not work after restoring a snapshot, in this case un-installing Notepad++ then installing Download Microsoft Visual C++ 2008 Service Pack 1 Redistributable Package MFC Security Update from Official Microsoft Download Center and installing Notepad++ again then worked. Again with Windows Server 2012 R2 and Notepad++ 6.8.2 this was not an issue.
Starting with Notepad++ 6.8 the default font switched to "Source Code Pro", it used to be "Courier New". If you have upgraded from an old version you have to make the change manually, simply go to Settings -> Style Configurator..., then select "Global Styles" and change the font name for both "Global override" and "Default Style". With Notepad++ 6.8.2 the "Source Code Pro" font was dropped, it will come back at some point when the issues are sorted.
There are three possible options regarding networking in terms of Notepad++ connecting to the internet:
Direct Connection: if you have a direct connection to the internet or rather a proxy is not required then everything is fine out of the box
Proxy Connection: as of Notepad++ 6.3.1 you need to configure the proxy settings in the Plugin Manager, via the Settings button, you can also configure the Updater to use a proxy via "Set Updater Proxy" on the ? menu
No Network: in this scenario there is no point selecting "Updater" in the installer and any plugins will need to be updated via the Plugin Download section below
Install the following Plugins from the Plugin Manager:
When Notepad++ has been installed and the plugins fully installed then I like to make the following changes:
Sometimes it is useful to get Notepad++ to work as a Notepad replacement. There are ways to make it a full blown replacement, however sometimes it is enough to get it to work as the default application for text and log files. In which case open up the Preferences dialog, switch to the File Association tab, use the "Supported exts" part of the screen to highlight .txt and click the right arrow to move it to the "Registered exts" list, do the same for .log and you're done.
First, consult the Notepad++ wiki for details of what plugins are available and what they do, see Plugin Central - Notepad++ Wiki for details. This page contains links to the downloads for the plugins or their SourceForge project pages. However watch out as some link to old versions! So it is worth going to Notepad++ Plugins - Browse Files at SourceForge.net manually sometimes. The Compare plugin has it's own project page on SourceForge, however a number of plugins like TextFX and XML Tools are on the NPP Plugins SourceForge Project.
When you have downloaded the plugins, usually in zip format then extract the file archives. The DLL's should be installed in %ProgramFiles%\Notepad++\plugins, if there is any config then it should go in the plugins\config folder and documentation should go in plugins\docs. This should be done when Notepad++ is not running. When you have copied the files, start Notepad++ and the plugins should work just fine.
I also like to install firstobject XML Editor which is an excellent XML Editor but can be configured to launch from Notepad++. The launching from Notepad++ is in theory easy to setup, however I have never found it so, up to and including Notepad++ 6.7.9, so my recommended steps are these:
"C:\Program Files (x86)\firstobject\foxe.exe" "$(FULL_CURRENT_PATH)"