The newest troubleshooting guide is on post #829. The file address refers to the location of files and folders/directories on a computer's hard drive, not the content of files. I included that advice because of post #362, which resolves a 'The system cannot find the path specified' error. Post #820 explains how to edit the files of Angra Mainyu and Frey [Anti-Mind], which also works on other corrupted kamihime such as Nephthys [Anti-Mind] and Pruflas [Anti-Mind].
Edit 1: Updated to include both DLpy scripts, the troubleshooting guide (mentions the newest DLpy script location), and attached the DMM files for Maquia and [Memorial0020] Scheele. The previous DMM files are on post #829.
This error is usually from outdated scripts. Download the files from post #798 for the Nutaku player or from posts #570, #800, and #820 for the DMM player. Also, if you need a VPN to play the game you might need one to run the scripts. The attached troubleshooting guide goes into detail about some of the problems that can occur at each step of setting up the player for both versions.