Installing on Windows#

The novelWriter installer is not signed, so you will therefore be presented with security warnings when trying to install it on your PC. All this means is that Windows doesn’t know who created the install file.

Knowing where you download software from is important, so make sure you only download the installer from either here on the website, or directly from the project’s GitHub Releases page. All download links on this website also point to the GitHub Releases page. It is the only official source of downloads for Windows.


You can verify that you received the correct installer by checking the SHA256 sum. A SHA sum is a long number that is unique for a given file. It will only be identical for an identical copy of the file. The correct value is listed nearby where you downloaded the installer, either on the Home page or the Downloads page. You can also download the .sha256 file on the GitHub Releases page alongside the installer.

In order to get rid of the “Unknown Publisher” warnings in Windows, I would have to buy a code signing certificate that Microsoft accepts. They cost several hundred US dollars per year – for the cheap ones. This is a free app, and there is nowhere near enough donations made to this project to pay for that at this point.

Sometimes, Windows will try to prevent you from installing unknown applications. Below is a quick guide on how to disable the block for the novelWriter installer file.

Windows 11 and Windows Defender#

When you’ve downloaded the installer, and try to run it, Windows Defender may not allow you to run it. This is due to the missing signature, as mentioned above.

You can explicitly unblock the installer by going to your Downloads folder, find the novelWriter installer file, right click it, and select “Properties”.


In the “Properties” window that opens up, make sure you’re on the “General” tab, and check the “Unblock” check box at the bottom next to “Security”.


You should now be able to run the installer.

It will still show you this notification when you start the installation, again reminding you that the installer is from an “Unknown Publisher”. Select “Yes” to continue.


What’s in the Installer File?#

The installed files for novelWriter are usually located in:

C:\Program Files\novelWriter

Since novelWriter is written in pure Python, there is no executable binary file (.exe file). Instead, novelWriter comes with the official Python executable included. This executable is called python.exe, and is signed by the “Python Software Foundation”. Most of the other files in the main folder are also for Python. They are included in the installer from the Python Website when it is created.

The start script for novelWriter is called novelWriter.pyw, and all of the code for it is in the novelwriter folder. The app code is in a number of .py files, and they are all readable in for instance Notepad. There are also a number of .pyc files, which are performance enhanced versions of the .py files, generated by Python. If you delete them, they will be created again the next time you run the app.

In addition to its own code, novelWriter depends on a few libraries. They are located in the lib folder:

  • PyQt5 is the framework that novelWriter is built upon. It is a Python wrapper library for the Qt Framework.

  • lxml is an XML library currently used by novelWriter (it will be removed in release 2.1).

  • enchant is a spell checker library that provides spell checking capabilities for novelWriter.

That’s all.