Getting Started

Download the latest version of N2D22 from here and save it to your PC.
Extract the N2D22-winAnyCPUdotNet472*.zip file and open the destination folder.
Right click the file N2D22.exe and choose Properties.
At the bottom of the Properties window, you might see an option to Unblock.
If you see the option, tick the box and click OK. If the option isn't there, choose Cancel or close the window.
Double click on N2D22.exe to run it. If you see any security prompts, choose any option along the lines of OK, Yes, Allow, Continue, etc.

The application will check for Python and esptool.py. If prompted to install Python, choose Install Python 3.9.7 (Recommended).
The application will then check for esptool.py. If prompted to install esptool.py choose Install esptool.py (Recommended).
The application will repeat the check to ensure everything was installed correctly.
N2D22 will check your system for drivers. If drivers aren't found, you can try plugging your device in and proceeding anyway - Windows should install them automatically or through Windows Update. If the device isn't detected, install drivers manually.
Assuming your device is detected by the OS it will be detected by N2D22. You will be prompted to confirm it's the correct device, make sure to check the device name listed below the Found new device text. If satisfied, choose Use this device; otherwise, choose Don't use this device and N2D22 will ignore that device and continue searching.
Once the device has been selected, a connection will be established and N2D22 will read the MAC address of your device to verify the connection.

The application will then prompt you to choose your installation method. Get the latest image from the Internet (Recommended) will allow you to choose any version/revision from the official esp8266_deauther repository, download and flash it automatically. Alternatively if you wish to Use a local image on this PC you will be able to open an existing .bin file to flash your device with.
Once a file has been chosen, flashing will begin. The application will erase the flash memory of the device and write the new image to it. It's important that you don't disconnect the device while flashing. Doing so will corrupt the software and you risk bricking the bootloader which means you won't be able to re-flash it again rendering the device useless.

Remarks

Selecting Don't use this device will prevent the device from being used at all during the session. If you want to change your mind, you'll need to restart the application.

If you choose not to install Python and/or esptool.py the application will restart in Portable mode.
You can start in Portable mode by using the --portable flag as an argument in the command-line.
If you wish to use this mode; before running the program, copy the esptool.exe from the legacy folder into the same folder as the N2D22.exe before running with the portable flag. Otherwise you will be prompted to locate the esptool.exe in which case, you can also browse to the legacy folder, select it and click Open.