Ok - let's make things short. Odoo is using Wkhtmltopdf dependency to print pdf files. If you installed Odoo and haven't installed Wkhtmltopdf then you won't be able to print pdf and your customers won't be able to finalise their transaction in some cases (they will get "Internal Server Error"). This tutorial will show you how to install and configure Wkhtmltopdf with Odoo 12 and Ubuntu Linux 18.04
It is an open source tool to render HTML to pdf.
The installation may be as simple as:
pip install wkhtmltopdf
However, with Odoo it is a bit more complicated.
Visit the official page here.
Wkhtmltopdf & Odoo
Depending on the version of Odoo you are using as well as
Information on supported Wkhtmltopdf and Odoo versions you can find on https://github.com/odoo/odoo/wiki/Wkhtmltopdf.
Let's install Wkhtmltopdf
As mentioned before this tutorial will base on the Odoo 12 installed on Ubuntu Linux 18.04
Before you start - make a backup. It is easier to restore the instance than fix it. If you are already a superuser, you don't need to type sudo in fornt. First download the package:
sudo wget https://builds.wkhtmltopdf.org/0.12.1.3/wkhtmltox_0.12.1.3-1~bionic_amd64.deb
Unpack it:sudo dpkg -i wkhtmltox_0.12.1.3-1~bionic_amd64.debInstall:sudo apt-get install -f
sudo ln -s /usr/local/bin/wkhtmltopdf /usr/bin
sudo ln -s /usr/local/bin/wkhtmltoimage /usr/bin
The reason for this tutorial is to put more light on the case. I have already written one on this topic and it can be found https://cier.tech/blog/odoo-tutorials-1/post/odoo-warning-wkhtmltopdf-failed-error-code-11-2
How to install Wkhtmltopdf
Solve 'Unable to find Wkhtmltopdf on this system'
Odoo Technical Tutorial