• Download De_DRM_tools from https://github.com/apprenticeharper/DeDRM_tools• Unzip De_DRM_tools-master.zip

• Within the new folder DeDRM_tools-master, navigate to \Other_Tools\Tetrachroma_FileOpen_ineptpdf

• Right click and open the file ineptpdf_8.4.51.pyw and read the instructions in the # comments. Additional files to install are:

o Python 2.7 (latest version available is 2.7.17 - recommended to use 32bit version over the 64bit, not sure why)

o PyCrypto

o PyWin extension

o FileOpen plugin

• Install Python 2.7 from http://www.python.org/download/ or directly from https://www.python.org/ftp/python/2.7.17/python-2.7.17.msi

• Open Command Line in the folder C:\Python27\Scripts -> This can be done by navigating to C:\Python27, hold shift, right click on Scripts and press 'Open command window here'

• To install PyCrypto, type pip install pycryptodome o Note installing pycrypto via 'pip install pycrypto' will produce an error as pycrypto libraries themselves are unupdated, but pycryptodome is updated

• To install the PyWin extension, type pip install pywin32

• To install the FileOpen plugin, go to https://plugin.fileopen.com/ and install the latest version

• Navigate back to the folder C:\Users\XX\Downloads\DeDRM_tools-master\Other_Tools\Tetrachroma_FileOpen_ineptpdf

• Right click on ineptpdf_8.4.51.pyw

• Navigate to line 2285 and change the value of x in 'self.fileopen['Build']='x' to the build number as shown on the FileOpen plugin page (Windows Installer link)

• Double click on ineptpdf_8.4.51.pyw

• Ignore the Password or Key file box, press the dots to add an input file, type the name of the decrypted output file and press decrypt

• Decrypted file will appear at C:\Users\XX\Downloads\DeDRM_tools-master\Other_Tools\Tetrachroma_FileOpen_ineptpdf